Here is a simple, yet useful homebrew app for anyone who prefers running an older firmware version; whether it be 1.50, or an aged version of Dark_AleX’s OE. The concept is simple: flash the bundled index.dat & version.txt files from a later firmware version. Many newer PSP titles/demos require the most recent, so this should result in a successful launch. It also creates a backup and provides a method to restore your original files. Straight forward, and to the point.

Thanks to http://www.dcemu.co.uk for the news.

http://www.psp-hacks.com/2007/09/07/version-flasher-17/