my psp was at 3.90 m33 and i updated to 4.01 m33-2 (useing modded files) but i skipped 4.01 m33-1... so i can't play any of my emulators or custom software.....
internet update is the same things as updating its just easier. Just install the 1.50 add on using gamblers tut on here and you will be able to work them again