What is the Use of the .cso File Extension?

.cso files represent the compressed ISO image format and are used for archiving PlayStation Portable games. The .cso file type includes various compression levels, from 1 to 9. However, choosing higher compression levels may lead to slow loading of the disk image.

The .cso compression method was the first compression method for the ISO image format. A .cso file is commonly referred to as a Compressed ISO Disk Image, and these files come under the category of Disk Files.

Names of the programs that can open .cso files

If you use Windows, you may use any of the following applications to open a .cso file:

  • PSP ISO Compressor
  • UMDGen
  • CiSO Converter

If you use a Mac OS, you may use the following applications to open a .cso file:

  • Prometeus

Can .cso files be converted into other disk file formats?

Yes, tools are available, such as PSP ISO Compressor that allow users to convert a .cso file into other disk file formats.

What to do when you receive a file type error while opening a .cso file

Commonly, a file type error occurs when any of the following conditions hold true:

  • The program that opens the file you are trying to view is not installed.
  • The file you are trying to view is corrupt.
  • File openers on the Windows system are corrupt or damaged.

To view the desired file, we recommend you install a reliable File Extension Repair tool and use it to open the desired .cso file. File extension repair tools, not only fix the issue of damaged file or corrupt file openers, but may also allow users to view files even when the required software is not installed.