I am running my psp on 3.03 oe-c and i am having a problem with a brand new 4GB memory stick pro duo. I have formatted the stick however when ever i run any iso i get either the error 80020321 (if i'm using no umd enabled in the recovory menu) or error 80020148 (if i'm using a umd in the drive). This even more strange due to the fact that on my 1Gb card i can run any iso i want including the iso's having the error's on the 4GB card. I have searched around and found that there is some sort of problem with the 4Gb Datel hard Drive getting the same error so i wondered if this was related. Any help would be great!