The table below provides useful information about the .a15 file extension. He answers questions such as:

• What is a file. a15?
• What software do I need to open the . a15?
• Like a file. a15 be opened, edited or printed?
• How to convert. a15 files to another format?

We hope you find this page a useful and valuable resource!

0 extensions and 1 aliases found in the database

✅ ARJ Compressed Archive

Description (in English):
ARJ file is an ARJ compressed archive. It is the native format of ARJ(dos) and WinARJ archiver. like other archives, ARJ files are data containers, they store one or several files in the compressed form.

ARJ format description not yet available

MIME type: application/x-arj-compressed

Magic number: -

Magic number: -

Sample: -

ARJ aliases:

a00, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15 , a16, a17, a18, a19, a20, a21, a22, a23, a24

ARJ related links:

ARJ related extensions:

Other file types may also use the file extension .a15.

🚫 The .a15 file extension is often given incorrectly!

According to Search on our site, these typos were the most common in the past year:

15 , aw5 , a1 , z15 , a51

Is it possible that the filename extension is incorrect?

We have found the following similar file extensions in our database:

🔴 Can't open file .a15?

When you double-click a file to open it, Windows checks the file name extension. If Windows recognizes the filename extension, the file opens in the program that is associated with that filename extension. When Windows does not recognize the file name extension, the following message appears:

Windows cannot open this file:

Example.a15

To open this file, Windows needs to know which program you want to use to open it...

If you don't know how to set up file associations .a15, check .

🔴 Is it possible to change the file extension?

Changing the file name of the file extension is not a good idea. When you change the file extension, you change the way programs on your computer read the file. The problem is that changing the file extension does not change the file format.

If you have useful information about the file extension .a15, !

🔴 Rate our A15 page

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You received a file by e-mail, but you can't view it, it won't open. What to do?
First, check it with a reliable antivirus program. If it does not find anything suspicious, then your computer either does not have the corresponding program, or it is not configured for the extension of this file.

(The extension is a series of letters or numbers after the dot in the file name (such as "jpg" in the name of the image file Picture.jpg).

By default, Windows does not display extensions for most standard file types. These include all files for which suitable programs are installed on the computer. For them, Windows shows only the name, and depending on the extension, the system selects the desired icon for the file)

For example:

1. You have been sent a WORD document file with the extension DOCX , and you have an old WORD 2003 program on your computer, which only works with files with the extension DOC and of course it will not show you this document, you need the WORD 2007 or 2010 program.

2. You downloaded an e-book in the format djvu , you will not be able to read a book until you install a program that works with this extension.

A very convenient site is the Directory of file types. Description of file extensions. How to open files of various formats.

Press the button and you will go to a site that will help you determine the program for any extension. In the search bar, write the desired extension.

Do you want your computer to show the extensions of all files? Give him the appropriate instructions.

Windows XP
1. Click on the buttons Start -> My Documents.
2. Then select menu items Tools -> Folder Options and in the window that opens, click on the tab View.
3. Uncheck the option Hide extensions for known file types,

If our system cannot cope with the .15 extension and failed all the automatic and semi-automatic methods of teaching it this art, it remains to manually edit the Windows registry. This registry stores all the information related to the operation of our operating system, including the connection of file extensions with programs for their maintenance. Team REGEDIT inscribed in the window „search for programs and files” or "run in the case of older versions of the operating system, gives us access to the registry of our operating system. All operations carried out in the registry (even not very complex ones regarding the .15 file extension) have a significant impact on the operation of our system, therefore, before making any modifications, you should make sure that a copy of the current registry is made. The section we are interested in is the key HKEY_CLASSES_ROOT. The following instructions show, step by step, how to modify the registry, specifically the registry entry containing information about the .15 file.

Step by step

• Press the “start” button
• In the "find programs and files" window (in older versions of Windows it is the "Run" window) enter the "regedit" command and then confirm the operation with the "ENTER" key. This operation will launch the system registry editor. This tool will allow not only to view existing records, but also to modify, add or delete them manually. Due to the fact that the registry of the Windows system is key to its operation, all operations carried out on it should be performed judiciously and consciously. Careless removal or modification of an inappropriate key can permanently damage the operating system.
• Using the ctr+F key combination or the Edit menu and the "Find" option, find the extension you are interested in.15 by typing it in the search engine window. Confirm by pressing OK or using the ENTER key.
• Backup copy. It is extremely important to back up the registry before making any changes to it. Each change has an impact on the operation of our computer. In extreme cases, an erroneous modification of the registry can make the system unable to restart.
• The value you are interested in regarding the extension can be manually edited by changing the keys assigned to the found extension.15. In this place, you can also create the necessary entry with the a.15 extension yourself if this is not in the registry. All available options are in the submenu (right mouse button) or in the "Edit" menu after placing the cursor in the appropriate place on the screen.
• After you finish editing the entry for the .15 extension, close the system registry. The introduced changes will come into effect after restarting the operating system.

The computer works with information, which can be textual, graphic, audio or video format. All information processed on a computer is stored in files. The concept of a file is one of the basic concepts of computer literacy.

File is a named area of ​​memory on a computer storage medium. In other words, a file is a set of data on a computer medium (hard disk, CD and DVD disk, flash drive, etc.), which has its own name ( File name).

What characters can be used in a file name? It is recommended to use Russian and Latin letters, numbers, spaces and punctuation marks in file names. However, the file name must not begin with a dot, and must not include square or curly ( ) brackets in the name. The following service characters / \ | : * ? “< >

Is there a maximum length for a filename? The length of the file name must not exceed 255 characters. In fact, 20-25 characters are usually enough.

Windows does not distinguish between lowercase and uppercase letters for filenames. This means that it will not be possible to store files in the same directory whose names differ only by case. For example, two file names "Name.doc" and "NAME.doc" for Windows will be the same name for the same file.

Do you think there can be several files in the same directory with the same name PRIMER? This is possible provided that the name PRIMER has different extensions.

File name extension points to file type(sometimes they say - file format). Thus,

• "file type",
• "file format",
• "file extension",
• "file name extension" -

it is, by and large, the same thing.

For example,

PRIMER.doc(x) - the file type is a Word document (or a file in Word format),

PRIMER.bmp - the file type is a picture,

PRIMER.avi - the file type is a video file,

PRIMER.wav - The file type is an audio file.

All these files have different names (due to different file name extensions) and can be stored in the same place, i.e. in one directory. If we draw an analogy with the names of people, then the file name is the same as the name of the person, and the file name extension is the same as the last name of the person. Accordingly, PRIMER.doc and PRIMER.bmp by this analogy are the same as Ivan Petrov and Ivan Sidorov. Files named PRIMER.doc and VARIANT.doc are two brothers from the same document family (with the same .doc extension), just like, for example, Ivan Petrov and Fedor Petrov are brothers from the same Petrov family.

A filename extension is the part of a filename that starts with a dot followed by a few characters.

Three-letter extensions are common - .doc, .txt, .bmp, .gif, etc. Case does not matter, so .doc and .DOC are the same document extension.

The extension is an optional attribute in the filename, i.e. it may not be. In this case, the dot is usually not put at the end of the file name. The extension, although not necessary, is still desirable, because. it tells Windows what type of file it is. Simply put, the file type is a clue to Windows which program should open the file. For example, the .doc extension indicates that the file should be opened with Word, and the .cdr extension indicates that the file should be opened with the Corel Draw graphics program.

There are reserved (service) names that cannot be used as filenames, since they are device names:

PRN - printer,

COM1-COM4 - devices connected to serial ports 1-4,

AUX - same as COM1,

LPT1-LPT4 - devices connected to parallel ports 1-4 (usually printers),

CON (consol) - on input - keyboard, on output - screen,

NUL is an "empty" device.

Here are examples of filenames that are invalid:

5<>8/7.txt - characters "<», «>" and "/" are prohibited,

What's the question? - symbol "?" prohibited,

PRN.bmp - Here PRN is a reserved name.

Depending on the type of file, different icons (icons) are displayed on the Windows screen:

Windows Explorer (Start-Programs-Accessories-Explorer) by default has a mode when file name extensions are not displayed on the screen, but file icons (icons) are displayed.

When saving a file, it is enough to write its name and select the file type from the available list. The selected extension will automatically be added to the file name. For example, in the figure below, the program itself will add the .jpg extension to the file name. As a result, Windows will remember this file with the name "picture in paint.jpg".

When saving files, always pay attention to the "file type" line, if any, to avoid confusion. After all, the file type is a hint for Windows, with the help of which the system determines which program this file can be opened.

If you have downloaded a file from the Internet, for example, with the .rar extension, but you do not have an archiver program installed on your computer to work with such “compressed, archived” files, then do not be surprised that the file does not open. In other words, you must be aware that if you open files, for example, in video format, then the computer must have an appropriate program for working with this format.

An analogy can be drawn between a file (more precisely, between a file type) and a program that works with that type of file. The file is the lock, and the program that opens the file is the key. A lock without a key will not open, and a key without a lock is of no particular value.

Computer literacy exercises:

1) Try to create two folders on your desktop named PRIMER and primer. To do this, on the Desktop, right-click on an empty space, and in the window that appears, click on the “New” option and, finally, click on the “Folder” option. Instead of the words "New folder", enter "PRIMER". Then you repeat all this to create a second folder called "example". Did Windows give you the go-ahead to open a second folder?

2) Go, for example, to the Word editor and try to save the document with the name PRN. Did Windows allow such a name for the new file?

3) How to solve the problem: “I download files from the Internet, but they are in the xsd (PM) / RAR format and cannot be opened or read on the computer. What to do?"

P.S. The article is over, but you can read more:

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The DAT format is an extension for storing raw data of any type (from normal binary values ​​to encrypted malware code). A file with this format can be created by most programs.

Extension Features

The DAT file does not have an icon, and when trying to run the file, the operating system will prompt the user to select an application to open the document on their own.
In Windows OS, users often encounter DAT files that periodically appear on the desktop or in My Documents. Documents with title WinMail.dat or MailExchange.dat- these are objects that are created by mail clients and instant messengers installed on the PC. They store the history of correspondence, attached files and data about the user's contacts.

Programs to open DAT files

The DAT extension cannot be manually opened by the user. You can view the contents of the file only in a text editor or with the help of the program that created it. As a text editor, you can use the standard Windows Notepad, Notepad++ or any other text editor.

Most likely, the contents of the DAT will be encrypted, so the user will not be able to understand what the file is doing. You can view the function of an object in the program that generated it.
If you don't know which program generated the DAT, try the following applications one by one or open Dat online.