Ok, TC, read this, and read it good.
1. Update you psp to 4.01 M33. NOW. If it's a phat, also install the 1.50 kernel to run homebrew, etc.
Do not upgrade to 4.01-2 M33. STAY AT 4.01. I had too many issues with 4.01-2. No problems with 4.01.
(This is
MANDATORY if you want PSP to work) Also, dont be afraid of some apps not working. as long as you have eloader or 1.50 installed, it should play fine.
2. rename you Phantasy Star Portable FOLDER containing your
Eboot.pbp &
File.FPB to this:
ULJM1014
now it should run. I had the same problem, that error, because the folder wasnt named properly when I DL'd it.
I got it from somewhere else, and it had that code, as if it was a PSN store code. Once I had that, I tried renaming my original version of PSP and it magiaclly started working.
So, have fun. I cant wait till this game comes out, by the way