The prefetch folder is a subfolder of the Windows system folder. The prefetch folder is self-maintaining, and there's no need to delete it or empty its contents. If you empty the folder, Windows and your programs will take longer to open the next time you turn on your computer.

What happens if I delete prefetch files?

Deleting Prefetch Files. ... Prefetch files are automatically created to speed up the launch of certain applications and don't usually take up much space on your drive. There's no real reason to delete these files unless you need to free up a small amount of space.

Should I delete old prefetch data?

Their purpose is to open applications faster, but the actual benefit is very minimal (IMO). You should delete them sometimes, because as the time goes by, the Prefetch directory can become very full and there for actually slow things down.