If you are faced with the problem that the Windows XP operating system does not load, then first of all you need to find out the nature of the breakdown.
There are two variants of the problem:
- Software error due to software malfunction.
- A hardware error caused by the failure of a specific part.
1. The computer responds, but does not boot
You pressed the Power button, and nothing is displayed on the monitor, but the cooler is working and the lights come on? Most likely the monitor is not connected correctly or a hardware error has occurred. What to do if the matter is still in the hardware part?
Alternatively, contact has disappeared somewhere in your PC due to clogging with dust. Then you should do the following:
- Unscrew the cover from the system unit and remove the video adapter and RAM.
- Carefully remove dust on the parts and the system unit itself.
- Thoroughly wipe the contacts of the video adapter and RAM.
- Put all the parts back and check if the computer works.
If after the steps taken, the computer does not turn on and Windows XP does not boot, you will need to find the part that is out of order. This can be easily done using the BIOS (Basic Input / Output System). The main thing is to know which version is installed on the computer.
Each time the PC boots, it is checked using the BIOS. If any failure occurs during the test, the computer emits a sound, by the type of which you can find out the cause of the failure. You can find out what kind of breakdown a certain sound signal is talking about from the BIOS signal table.
If you do not know what version of BIOS you have, then you will have to suffer. You will need to change your parts one by one to others (borrowed from someone) until it becomes clear which one is inoperative. Is this option not feasible for you? Then it only remained to turn to specialists.
2. The computer does not respond at all
In the case when you press the Power button, but the computer does not respond (the cooler does not make noise, the lights do not light up), you should immediately check if the computer is connected correctly. To do this, make sure that the switch on the back of the system unit is turned on and carefully examine the power cables.
If everything is connected correctly, then most likely the power supply has broken. If you have never dealt with electrical appliances, it will be quite difficult to eliminate such a breakdown yourself. But it would still be nice to borrow a power supply from someone, connect it to your PC and check if it turns on. Not sure how to connect? Then it is worth contacting specialists.
3. The computer turned on, but Windows XP does not start
There are times when the PC is turned on, the monitor is working, but Windows XP does not load (black screen). The screen displays a window as in (Figure 1).
Figure 1 - DISK BOOT FAILURE - INSERT SYSTEM DISK AND PRESS ENTER
If you see such a message, it means that the computer cannot find the storage device on which the OS is stored. Simply put, the computer does not see the HDD, therefore Windows XP does not boot.
First of all, find out if the hard drive is connected correctly. If everything is fine with the hard drive, then the operating system has become unusable and you will have to reinstall Windows.
You can also see the text as in (Figure 2) when the computer starts up.
Figure 2 - Message
This means that the system files are lost or damaged. In this case, you need:
- Load the last successful configuration. To do this, you need to turn on the computer and press F8 on the keyboard. Then select the required item from the displayed menu.
- Follow the steps above, but click on "Safe Mode". Perform a system restore if the OS boots.
If the operating system does not boot at all, then it is most reasonable to reinstall Windows XP.
As a service center engineer, I often hear complaints from customers that the computer does not start or boot. This is how they describe various problems - from problems with switching on to a violation of loading the operating system. But to be more precise, “does not start” should be understood as does not turn on, does not initialize or does not work, while “does not boot” should mean exactly problems with the system boot.
Let's look at examples of specific symptoms why the computer does not start.
No response to pressing the power button
Causes
- There is no voltage in the mains, the electric cord is damaged or the power supply unit is out of order.
- Power button damaged.
- There is no electrical contact in the power connectors.
- The power management chip is out of order.
- Internal power supply damaged (on laptops).
- The chipset is out of order.
- BIOS is corrupted.
What to do?
- Make sure there is voltage in the mains. Check if the power supply is turned on and the cable is securely connected to it. If possible, test the computer with a different power supply.
- To test the button, disconnect the wires from the Power Switch contacts (ON, PWR_ON, PC_ON) on the motherboard and close the contacts with a screwdriver. If the PC turns on normally, the button is to blame.
- Reset the BIOS by removing the CMOS chip battery and short-circuiting the socket pins. Or using the Clear CMOS jumper (button) (other names - CLRTC, CRTC, CL_CMOS, CCMOS).
The computer turns on (fans are running), but nothing appears on the screen
Causes
- The processor is defective or there is a problem in its power supply system.
- The north bridge is out of order.
- Defective strips, slots or power supply of RAM (random access memory).
- The BIOS firmware has crashed.
What to do?
- Make sure the processor is not damaged and its cooling system is properly connected.
- Check if the additional 4-pin connector near the CPU power supply is connected.
- Check the operation of the RAM strips in different slots, try replacing them with known good ones.
- Reset BIOS settings.
Computer shuts down or restarts during startup
Causes
- Overheating of the processor or main components of the system board.
- Failure (short circuit) of one of the computer devices.
- The voltage levels on the motherboard are out of range.
- BIOS problems.
What to do?
- Clean the cooling system from contamination. Refresh the thermal paste layer on the processor.
- Disconnect all devices that are not necessary for starting the computer: peripherals, expansion cards (sound, network, etc.), optical drive, everything connected to USB (except for the keyboard), RAM (except for one bracket), hard drives, except for the system ... If the PC starts, one of the disabled devices is to blame.
- Reset BIOS settings.
Operating system loading does not start
Causes
- The system hard drive has failed, is not properly connected, or is not receiving power.
- Chipset (South Bridge) problems.
- BIOS problems.
- Corrupted MBR or operating system boot files.
What to do?
- Make sure the hard drive is properly connected, functional, and receiving power. Check if it is detected in BIOS and visible when booting from other media.
- Reset BIOS settings.
If all else fails, and also if the problem with switching on occurs on the laptop, contact the service.
Let's talk in more detail about the problems associated with the Windows XP operating system.
Why might Windows XP fail to start?
There are many reasons why Win XP won't load. These include damaged or missing boot files, registry changes, incorrect boot.ini configuration file settings, MBR (Master Boot Record) corruption, and sometimes a combination of these factors. These problems arise most often due to the following:
- viral activity, especially associated with blocking the MBR and Windows desktop, as well as due to unsuccessful attempts to cure such viruses;
- errors when creating a configuration with loading multiple operating systems;
- surface defects of the hard disk;
- power outages that damage Win files during the read and write process.
For a better understanding of the causes of Win XP boot failures, let's briefly analyze how this process goes.
How to boot a computer running Windows XP
Before the system stages of turning on the PC - receiving a Power Good signal by the motherboard, initializing devices and starting the execution of the BIOS code, we will not consider, since the problems at this stage relate to hardware. The beginning of the start of Windows will be considered the execution of the MBR boot code, which transfers control to the BIOS. So.
- The MBR finds the active partition in the table and transfers control to the boot code from its first sector (Boot Sector).
- When executed, the boot sector code transfers control to the NTLDR file, the Windows XP boot loader.
- NTLDR puts the processor in 32-bit mode and checks if a hibernation image (hiberfil.sys file) is saved on the hard disk. If there is such an image, it loads it, if not, it reads information from the Boot.INI - the boot configuration file.
- If multiple copies of Win are installed on the computer, a menu is displayed from which the user can choose which system to boot.
- After selecting the system, the ntdetect.com file is launched, which determines the hardware configuration of the current boot.
- Next, the files ntoskrnl.exe (Windows XP kernel) and Hal.dll (Hardware Abstraction Layer) are loaded - an intermediary between the PC hardware and the Win kernel.
- The last task of NTLDR is to start drivers marked as bootable in the registry and transfer control to the kernel code. At the same time, the equipment is initialized, the interrupt controller and the I / O system are turned on.
- The Windows XP kernel starts the session manager - Smss.exe, which creates the user environment, the graphics subsystem - Win32k.sys, the client-server execution subsystem Csrss.exe, the Win logon program - Winlogon.exe, the authentication service - Lsass.exe, and Services.exe - Service Control Manager.
- This is followed by the launch of the welcome screen - LogonUI.exe and the user logon program in Windows - Userinit.exe.
- Next, the explorer (Win shell) - Explorer.exe is launched, the desktop appears on the screen and the system goes into standby mode for user commands.
How to restore boot Windows XP
Win boot failure can occur at any of the listed stages. Knowing what follows what, it is easier to understand the reasons that disrupt the launch of the system.
Master boot record (MBR) repair
If the MBR is damaged, Windows XP startup is interrupted at the very beginning, almost immediately after the computer is turned on. It is manifested by the fact that a message is displayed on the screen:
- Missing Operating System - the operating system was not found;
- Invalid Partition Table - invalid (defective) partition table;
- Error Loading Operating System - error loading the operating system.
Or nothing is displayed.
If the MBR is damaged, both the boot code and the partition table can be damaged. To recover the MBR code, you need to start the computer from the Windows XP installation disc and enter the recovery console. For this:
- put the installation disc into the drive and start booting, when you see the message “You are welcomed by the installer”, press the R (restore) key;
- to work in the console, specify the serial number of Win XP where you want to log in. If you have one system, press 1;
- enter the administrator password;
- enter command fixmbr and press Enter - the boot code will be overwritten;
- to exit the console, enter the command exit.
The partition table cannot be fixed by Win's own tools. To do this, you have to use third-party programs. One of these is a utility TestDisk, does an excellent job with this task.
Restoring the boot sector and NTLDR boot loader
Boot sector code corruption has the same symptoms as MBR corruption, and error messages can be as follows:
- NTLDR is missing - NTLDR loader was not found;
- And disk read error occurred - a disk read error occurred;
- NTLDR is compressed - NTLDR loader is compressed (not unzipped).
To solve this problem, you will need the Recovery Console again, where you will need to run the command fixboot.
The same messages may appear if there is no NTLDR loader in the Windows XP root directory. A copy of this file transferred from another computer running Windows XP or from an installation disc will help to fix the situation.
Boot Configuration Setting (Boot.INI)
If the boot configuration file Boot.INI contains errors, Win XP will also be unable to start, since NTLDR will not know what to boot and with what parameters. The system notifies about this problem with the following messages:
- Check boot path and disk hardware - check the disk and the path to the boot partition;
- Could not read from selected boot disk - could not read data from the selected boot disk;
- Windows could not start because of a computer disk hardware configuration problem - Windows could not start because of a disk configuration error.
The Recovery Console will help you out of the situation again. Run the command: bootcfg / rebuild- it restores the default boot.INI records. In the course of its work, all partitions of the hard disk are checked for installed copies of Win. If systems are found, records about them are added to the configuration file, and the user can confirm or deny adding the system to the boot list. This way it is possible to restore the launch of several copies of Windows at once.
Registry repair
Another reason why Windows XP won't load is registry corruption, especially the System keys, which contain information about starting drivers, and Software, which contains boot control options.
To "roll back" these two partitions to the state at the time of system installation, start the recovery console and run the commands:
rename c: windowssystem32configsystem system.old
rename c: windowssystem32configsoftware software.old
copy c: windowsrepairsystem c: windowssystem32configsystem
copy c: windowsrepairsoftware c: windowssystem32configsoftware
In the same way, you can restore other Win registry keys: Defoult, Security and Sum.
Recovery of boot files
You already know why the files responsible for starting Windows XP lose functionality. Win in such cases is loaded almost to the end, but at some point it goes into reboot or ends with BSoD. So, error 0xC000021a (fatal system error) indicates the absence or damage of Winlogon.exe or Csrss.exe. Problems with other files may not be accompanied by messages, but only show up as a black screen during the boot process.
If you know which files are missing, you can transfer them from another similar system or from the distribution disk - from the i386 folder. To do this, the computer is also booted from the Recovery Console, where the commands for copying and unpacking files from the storage are executed. So, the command expand d: i386userinit.ex_ c: windowssystem32 will unpack and copy to a folder system32 file userinit.exe where d: is the installation disk.
If you do not know what files Windows doesn’t load, installing the system in recovery mode will help. System files will be overwritten, while programs, settings, and user data will remain unchanged.
- Start your computer from the installation disc. When the “Welcome to the program…” window appears, continue with the installation by pressing Enter.
- In the course of further work, the program will scan the disks and if it finds a copy of Windows XP on them, it will offer to restore. To do this, select it in the list and press “R”.
- After the reboot, several more stages will pass, where user participation is required. Including - entering the serial number.
- At the end of the operation, the files will be overwritten, and if the reason why Windows did not boot was in them, the system will restore its work.
Using a Windows Boot Floppy
The first thing to refer to when a problem occurs during system startup is the boot floppy. It can help if the active partition of the hard disk or the files required to boot Windows are damaged.
In order to create a bootable Windows diskette, insert the floppy disk into the disk drive of the machine with the Windows XP operating system working correctly and configured in a similar way, open the My Computer window, click on the diskette icon and select the Format "(Format). In the Format dialog box, keep the default settings and click the Start button. Upon completion of formatting, close the window in order to return to "My Computer", double-click on the shortcut of the C drive and copy three files from its root directory to the floppy disk:
Boot.ini
NTLDR
Ntdetect.com
Now insert the created boot floppy disk into the floppy drive of the computer with the damaged system and click to restart the computer. When started from this floppy, the system will try to boot, ignoring the active hard disk partition and boot files.
Using the Last Known Good Configuration option)
You can also try starting the system using the Last Known Good Configuration option, which will undo any changes that caused problems in the CurrentControlSet registry key, which is responsible for determining hardware parameter values and installed drivers. The Last Known Good Configuration option will replace the contents of the specified registry key with the data from the backup that was used when the OS was last successfully started.
Restart your computer by clicking. When you see the message “Please select the operating system to start” or hear a single beep, press the key to launch the Windows Advanced Options menu. Select Last Known Good Configuration and press.
Note that you only have one attempt to restore the last known good configuration. In other words, if the option did not help to fix the system boot problem, then the backup is also corrupted.
Using System Restore
Another useful tool for troubleshooting Windows XP boot problems is System Restore. It runs in the background as a service to continually check critical system components for changes. Before changing any parameter, the service immediately creates a backup copy of it and a restore point. In addition, by default, checkpoints are generated every 24 hours.
To use the System Restore utility, restart your computer by clicking. When you see the message “Please select the operating system to start” or hear a single beep, press the key to launch the Windows Advanced Options menu. Select Safe Mode and press.
After booting Windows XP in Safe Mode, click the Start button and go to the Programs | Standard | Service | System Restore (All Programs | Accessories | System Tools | System Restore). In safe mode, only the option "Restore an earlier state of the computer" is available, since it is already selected by default, just click "Next" (Next). The Recovery Wizard will then prompt you to select a checkpoint and start the recovery procedure.
Using the Recovery Console
Windows XP boot problems of a more complex nature require, respectively, a more serious approach. The Windows XP Bootable CD contains the useful Recovery Console tool.
To start the system from a bootable Windows XP CD, insert it into the CD-ROM and click to restart the computer. Once the download starts, simply follow the directions that will allow you to select the core files to run Setup. At the Welcome To Setup screen shown in Figure A, press the R key to launch the Recovery Console.
The Recovery Console menu screen appears (Figure B). The folder with the operating system files is displayed here and a request to select the operating system that you want to enter. Press the corresponding number key, and then enter the administrator password. You now have access to the command line of the Recovery Console.
Rice. B
Fixing a damaged Boot.ini file
At the beginning of the Windows XP boot process, Ntldr uses the Boot.ini file to determine the location of the operating system files and whether options are available to continue booting. Therefore, if the Boot.ini file is damaged, Windows XP cannot start correctly.
If the system does not boot due to a damaged Boot.ini file, you can use the Bootcfg tool in the Recovery Console. Of course, to do this, you will have to start the system from a bootable CD and use the Recovery Console, as described in point 4.
To run the Bootcfg command, enter in the command line of the Operations Console:
Bootcfg / parameter
Where / parameter- one of the options below.
Parameters and Description
/ Add- scans the disk for all installed versions of Windows and allows you to add new OS identifiers to the Boot.ini file.
/ Scan- scans the disk for all installed versions of Windows.
/ List- displays each entry in the Boot.ini file.
/ Default- assigns the identifier set by default in the boot menu of the operating system as the main one.
/ Rebuild- completely recreates the Boot.ini file. The user has the ability to confirm each step.
/ Redirect- allows in administration mode without a monitor to redirect the download operation to a special port. Has two sub-parameters:
|
.
/ Disableredirect- Disables redirection.
Fixing a damaged hard disk boot sector
The boot sector is a small section of the hard disk that contains information about the operating system file system (NTFS or FAT32), as well as a very small program written in machine code that helps during the OS boot process.
If the system does not start due to a damaged boot sector, you can use the FixBoot tool in the Recovery Console. To do this, you will have to start the system from a bootable CD and use the Recovery Console, as described in point 4.
To run the FixBoot command, enter in the command line of the Management Console:
Fixboot:
Where
- the letter of the drive for which you want to create a new boot partition.
Fixing a damaged master boot record
The Master Boot Record occupies the first sector of the hard disk to start the Windows boot procedure. It contains the partition table and a small program called the master boot record that is responsible for placing the active or boot sector in the partition table. Once placed in the table, the boot sector begins to start Windows. If the master boot record is damaged, the active sector will not be able to start the system.
To fix this problem, the Fixmbr tool is provided in the Recovery Console. Start the system from a bootable CD and activate the Recovery Console as described in point 4.
To run the Fixmbr command, enter in the command line of the Management Console:
Fixmbr
Where - the distinguished name of the disk for which you want to create a new master boot record. For example, the distinguished name for the C master boot drive would be:
\ Device \ HardDisk0
Canceling automatic reboot
When a critical error occurs while using Windows XP, the system automatically reboots. If a crash occurs during the Windows XP startup process, the system gets stuck in an endless reboot loop. In this case, turn off the option to automatically restart on system failure.
When the system starts to boot and you see the message “Please select the operating system to start” or hear a single beep, press the key to launch the Windows Advanced Options menu. Then select Disable The Automatic Restart On System Failure and click. From now on, Windows XP will display an error message during the boot process, from which it will be possible to find out the cause of the malfunction.
Restoring from a backup
If you still can't get Windows XP to boot, you can try restoring the system from a backup (if available). The recovery algorithm depends on the backup utility used, which will provide all the necessary instructions.
In-place upgrade
If you can't get Windows XP to boot and there is no backup, you can perform an in-place upgrade. This operation is a reinstallation of the operating system in the same folder (as in the case of updating the version of Windows to a later version) and can fix almost all Windows boot problems.
Insert the Windows XP bootable CD into the drive and restart your computer. When the preparatory phase is complete, the Windows XP setup screen (shown earlier in Figure A) appears. Click to start the installation procedure. After a couple of moments, a page with a license agreement will appear, click to confirm agreement with the terms. Then the program will search for previously installed versions of Windows XP, and after it finds one of them, the second Windows XP installation screen will open (Fig. C).
Rice. C
To restore the selected version, press R, and to install a new copy of Windows XP -. In this case, the operation to repair the corrupted version is identical to an in-place upgrade, so press R. The installer will then check the hard drives for faults and then perform an in-place upgrade.
Please note that after an in-place upgrade or repairing a damaged installation, you will have to reinstall all Windows updates.
| Materials (edit) |
Often there are situations when the Windows XP operating system at one point stops loading. There can be many reasons for this, and each specific problem requires an individual solution. However, if the user knows why the computer may malfunction, then he can easily solve the problem on his own. All possible reasons for refusal can be conditionally divided into two groups:
- Hardware - something broke inside the computer and Windows no longer works;
- Software - there are software errors in the OS itself that interfere with the correct operation of the system;
It is also worth paying attention to at what stage the OS does not boot, that is, what manages to appear on the screen, and after which event you detect a failure. In this case, we will consider the situation when Windows XP no longer starts after the splash screen appears.
What can be done
The very first method to use is loading the system's last known good configuration. After all, the cause of the malfunction can only be that you, for example, installed an incorrect program or driver on your computer, due to the presence of which the OS does not load normally. Accordingly, for the system to work properly, you need to return it to the moment when these tools were not installed. The system registry contains a special section HKEY_LOCAL_MACHINES \ SYSTEM \ CurrentControlSet, where information about the last unproblematic boot is recorded. It is with the help of this section that Windows will determine the last known good configuration and boot from it.
Another option is to start Windows XP in Safe Mode.
With this method, only the minimum required set of software tools for Windows is loaded; none of the auxiliary programs are loaded.
If you could not boot your system as usual, but in safe mode it booted without problems, this already indicates that you most likely recently had some software installed on your computer due to which your system does not starts up.
After starting your computer in Safe Mode, you should restore Windows XP. To do this, you need to run the recovery utility, which is located in the All Programs / Accessories / System Tools / System Restore directory. It takes so-called snapshots of important system files, and saves the obtained information in the form of restore points, on which the system boots normally (more precisely, it was loaded before the problem occurred). Points can be created manually, from time to time they are created automatically (for example, after installing new software). You need to select the desired point and then start the recovery process. Upon completion, the computer will restart.
If all else fails
If previous attempts were in vain, and your system still won't boot, then the last step may be to restore the system using the installer. In order to do this, you need a Windows XP installation disc. Insert it into the floppy drive, enter the BIOS and put the boot from it. ... If a window opens on the screen prompting you to press any key to continue working, then do just that. The Windows XP installation window will appear. You will need the first item, by selecting which you will begin the installation of Windows XP on your computer. First of all, a license agreement will be displayed on the screen, which must be accepted, otherwise it will not work to install the OS.
At the next stage, the inscription "Searching for previous versions of Microsoft Windows ..." will appear at the bottom of the screen. Thus, the program determines what it needs to do next - install the system on the computer or start the recovery mechanism for an already installed OS. There is one rather important nuance - for the recovery procedure to be successful, you will need a disk with exactly the copy of Windows that you had installed earlier. This is due to the fact that each operating system has its own serial number, which during the installation process is also checked against the previously installed copy.
Let's say the check completed successfully and no compatibility issues were found. In this case, a message appears on the screen with a proposal to either restore the existing copy of Windows, or install a new copy on the hard drive, and skip the recovery procedure. Since we are interested in system recovery, we need to select the first item, and then press the R key. If suddenly the installation wizard prompts you only to install a new copy of Windows on your computer, do not agree - this will remove your OS from the computer and you will have to install it again.
If you did everything correctly, the program will start the recovery procedure. From the outside, it will look like installing a new OS on a computer, but in fact, this is exactly the restoration of a damaged system. After all, the process does not affect computer user accounts, programs installed on the computer and system registry data.
That's it, now your computer boots up normally. It is advisable to make sure that the correct boot priorities were set in the BIOS (because after restoring through the distribution kit, they have to be changed). Start from the hard drive should be prioritized. If everything is correct, then Windows XP will start up and run smoothly.
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Of course, firstly, what needs to be done is to determine the malfunction, since the computer can break down in two cases:
1. Hardware failure, i.e. when a part fails.
2. Software malfunction, that is, if there is an error in the software.
Option 1. The computer does not respond.
If nothing happens when you press the Power button, no indicators are lit, the fans are not spinning - first of all, we check that the computer is connected correctly. We inspect the power cords, check if the switch on the back of the system unit is turned on.
If everything is in order, then the most likely reason is the failure of the power supply. At home and in the absence of experience with electrical appliances, it is extremely difficult to eliminate this malfunction. However, if you have the skills to build a PC, you can borrow a power supply unit from a friend and test your computer. In other cases, it is better to contact a computer service center.
Option 2. The computer responds, but does not boot.
If, when you press the Power button, the power indicator (green light) is on, the fans are spinning, but nothing appears on the monitor - most likely there is a hardware failure (if, of course, the monitor is connected correctly). What can you try to do?
Perhaps your computer is clogged with dust and there is simply no contact somewhere. In this case:
1. Open the computer cover and remove the RAM and video card.
2. Carefully remove dust from the system unit and removed slots.
3. Wipe well the contacts of the RAM and video card.
4. Put everything back in and check if the PC is working properly.
If the actions taken do not work, you will have to look for a faulty part. It is easier to do this if you know the BIOS version installed on your PC.
If you do not know the version of your BIOS, then simply change the components one by one (borrowed from a friend). If this is not possible, the only way out is the same computer service center.
Option 3. The computer turns on, but Windows XP does not start.
If the computer turns on, an image appears, but WindowsXP does not load and a message like this appears:
DISK BOOT FAILURE - INSERT SYSTEM DISK AND PRESS ENTER.
This message indicates that no operating system storage device was found.
Check if the hard disk is connected correctly, if everything is correct, the operating system is out of order.
This problem is solved quickly and painlessly - by reinstalling (in some cases, restoring) the operating system.
This option is also possible:
In this case, most likely, there is a problem with the system files, or their damage, or complete loss.
You can take the following measures:
1. “Load the last known good configuration (with good parameters)”. To load the last known good configuration to Windows after turning on the PC, press the F8 key. In the window that appears, select this download item.
2. "Safe Mode". To do this, when you boot the computer, press the F8 key (as in the previous paragraph), select "Safe Mode", if the system boots, go to the following path: Start -> All Programs -> Accessories -> System Tools -> System Restore. And following the wizard's prompts, try to restore an earlier working system.
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