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File extension description in German
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File Extension BAK

Files with a file extension BAK are used to create a backup copy of a file. If you use Windows operating system, Windows automatically creates a BAK file as you are creating a file, such as a Word document. Windows also creates other backup files with the BAK extension, such as files which are necessary for booting up your PC or accessing different applications and programs.

Essentially BAK files are backup copies of documents, applications, programs, and other data on your PC. This type of file extension applies to both Windows operating system and Mac OS, and you must use the program that created the BAK file in order to view it in its original format.

How to Open BAK Files

Regardless if you use a Windows-based or Mac PC, it is important to remember you must use the original program for the BAK file. You must also change the file extension of the BAK file in order to view the file contents. Here is how it works:

If you have a document created with the word processing programs, such as Microsoft Word, you will end up with two files for the same document. One file will end with the extension DOC or DOCX if you have a more recent version of Microsoft Word, and the other file will be your backup file with the BAK file extension.

In order to view the file in the BAK format, it is necessary to change the extension to DOC or DOCX, so it is associated with the program that created it, Microsoft Word. To do this you simply click on Start on the main toolbar of your PC desktop and then choose My Computer from the pop-up menu.

When My Computer window opens, click on Tools on the upper toolbar and then choose Folder Options from the drop-down menu. Click on View in the new window and remove the check mark from Hide extensions for known file types and then click Apply and close the window. This will show all of the file extensions, so you can easily locate the BAK file.

Find the BAK file you want to view and then right click on it. When the drop-down menu appears, click on Rename and change the extension to DOC or DOCX to view the document in Microsoft Word. If you have Word 2007 or higher, the document extension will be DOCX. For older versions of Word prior to 2007, you can change the extension to DOC. Press the Enter key and open the file in Microsoft Word.