PSP will only boot with magic memory stick inserted

Ok so my nephews friend wanted me to hack his psp for him a few months ago which I did to CFW 5.00m33-6 He gave it back to me that same day saying that when he switched the memory card it stopped working and the screen would remain blank with the green power light on. I used the ultrapandora guide to make a mms and pandora battery from my psp and as soon as they were inserted into his it came right on I put in his battery but when I try to switch memory cards it won't work it goes back to doing what it was before. Did I miss a step in the guide or was there something else I was supposed to do? Any help is appreciated I've had his psp for quite a while and I'm sure he'd like it back asap. Thanks everyone.