.BK2 File Extension

A .BK2 file is a Windows Indexing Service Data File, created by Microsoft.

Open with Microsoft Windows. Available for Windows.

What is a .BK2 file?

The .BK2 file is a type of system file that is important for how your computer runs, specifically for a part of Microsoft Windows called the Indexing Service. This service helps your computer search for files and information faster by keeping track of them in an organized way. Think of it like a librarian who keeps a detailed list of every book in the library, so when you ask for a specific book, the librarian knows exactly where to find it. In this case, the "books" are your computer files, and the .BK2 file helps keep the list of those files up to date.

These .BK2 files are usually found in a special folder on your computer at C:\System Volume Information\catalog.wci\. This location is where Windows keeps a lot of important system information, and the .BK2 file stores data that Windows uses to help you search for files on your computer more quickly.

To open a .BK2 file, you would typically use Microsoft Windows itself, as it's a system file not meant to be opened by users in the same way you would open a Word document or a photo. It's part of the system's internal workings. However, it's good to know that these files, along with .BK1 files (which are similar in function), often have the name propstor.bk2. This specific name is used for files that play a role in storing properties or information about other files on your system to aid in searching and organizing them.


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