I jailbroke. installed categories and put all my apps in a folder. i unjailbroke and all my apps dissapear when i try to install them. what do i do!?!?!?
If you restore from back-up of when you had Categories installed that will happen. Restore from an older back-up.
Also, I know, I hate when people assume others used cracked apps, but... If they were cracked apps you are trying to install, they will not work on an unjailbroken iPod. Just try to restore from back up and it should work out
First off, Categories is amazing. Okay now that's out of the way there are two things you can do. 1. Re-jailbreak, install "Poof", un-poof all your apps, back up and restore again. Or you can just restore it and set it up as a new device.