What Is a CHK File?

Blizzard video game files cannot be opened in a third-party application.

The CHK file extension is used with more than one program. The files function differently in each program, and the CHK file from one program is not compatible with any other program. CHK files may be related to portions of Windows files, Blizzard video files or a specific anti-virus program.

Windows File Fragment

• When a user runs ScanDisk on her Windows computer, the program checks for bad files or clusters on the hard drive. If an unusable fragment is discovered, it is assigned the file extension CHK and segregated on the hard drive away from the rest of the data. The data associated with these file fragments is isolated and designated as containing an error, so you can usually delete CHK files without causing a problem.

Blizzard Game File

• The Blizzard Entertainment company applies the CHK extension to certain files associated with the video game StarCraft, a fantasy-themed game that is available for play on PCs. In the context of Blizzard, a CHK file contains a map in uncompressed format, and is included in the installer CD that comes with StarCraft. A StarCraft CHK map file can only be opened within the game.

Sophos Anti-Virus File

• Sophos also uses the CHK file extension to store information about virus definitions. CHK files are updated with InterCheck, a central virus database. A Sophos CHK file can only be modified by changing the reporting log and configuration of the InterCheck program. By default, these files are saved to the "Config directory" sub-folder within the "Program Files" folder. Sophos Anti-Virus programs can only be opened from within the program.

Generation and Deletion

• All of the CHK file types are either provided by the developer or automatically generated. A user without knowledge of the specific program to which the file belongs should not try to create a CHK file. If a file is altered or manually generated incorrectly, a user's computer may not be able to locate data because the file name is wrong. With the exception of Windows file fragments, CHK files should not be deleted, or necessary data may be lost.