Open SFCACHE File

An SFCACHE file is a cache file used by the Windows Operating System, starting with the Vista version, which at the user's discretion can be created on a flash memory device.

This functionality is actually adding virtual RAM, which Windows can access to help improve system performance.

You can use this through enabling ReadyBoost by right clicking on the icon of a flash memory device, then selecting 'Properties' and finally, clicking on the ReadyBoost tab by checking 'Use this device'.

This will create a temporary file called 'ReadyBoost.sfcache' on the flash disk.

Normally this file is hidden in the system and its size is configurable with the ReadyBoost application.

In order of data transfer speed, the physical RAM is first, as the fastest, then comes the SSD and flash memory and finally the conventional electromechanical hard disk. This is why ReadyBoost is used on flash drives.

SFCACHE files are part of the ReadyBoost function and considered system files, therefore they should not be opened, deleted or moved. To delete the SFCACHE file, you must disable ReadyBoost on the drive.