once you download and extract the app, you should have a folder that contains four other folders. IRSHELL, irshell150%, irshell150, and irshell271 providing you've downloaded irshell 3.1. the IRSHELL folder gets copied to the root of your memory stick > ms0:\. the irshell150% and irshell150 folders gets copied to ms0:\psp\game150. the irshell271 folder gets copied in ms0:\psp\game303 or you can place it in ms0:\psp\game. i have it running on my 3.10 OE-A'. if you need any other help just pm me.