I upgraded my psp 2006 from 5.00 m33-6 to version 5.50. Now it does not detect the games saved in my memory stick. What should i do?

Hello,
Try to clear the memory stick and reformat it with the PSP format and make sure that your current firmware version supports the ISO files saved in the game folders of your PSP.

you can only save full games on the memory stick if the game is pirated cs there are no full version games in the original .pbp format.you have to go somewhere they dea with games and is illegal(i.e not sony shop or somewhere big)cos downgrading your game is wrong and voids your warranty.NOTE:that odwngrading could destroy your game console

maybe you place it in the wrong folder..or memory card is busted

1. You need to download first ChickHEN R2 software from the internet and copy it to the PICTURE folder of your Memory Stick.
2. After that you need to run the ChickHEN software to update your PSP firmware version.
3. After that you need to copy the 5.03 GEN-C to your Memory Stick and run this update.
   

psp can only play games using the UMD drive, you can only play game demos using the memory stick.
Upgrade your psp firmware version to 5.00, it adds playstation store to the psp where you can buy and download full games onto your psp, all you need to do is create an account using the playstation store on your psp if you upgrade it to 5.00.

Use this link to help you upgrade you psp to 5.00
http://www.us.playstation.com/Support/SystemUpdates/PSP
don't forget to download psp media manager 3.00 on your pc.
use this link for psp media manager.
http://www.us.playstation.com/psn/mediamanager?LC-lps&FTTR=PSP_mediamanager_bottomleft_mediamanagerdetailpage

Good Luck. if you hacve questions write back.

HELLO! There's no need to downgrade ur PSP. If u have upgraded ur PSP from the official site and a official firmware has been installed on to ur PSP, it won't execute games(ISO,CSO) from ur memory stick. It will only run games from the UMD. If u want to run ur games from a memory stick u have to install a CUSTOM FIRMWARE. Try www.psp-hacks.com these guys have many softwares on their site. Dont worry its not that hard to put a Custom firmware onto ur PSP. 

Reformat Your PSP.

I think That's the solution

If you place costume frame work(CFW) you can upgrade the psp version very easy(and you can play all the games for free) ;)

You most likely need to format the memory stick with the PSP. What may have happened is once you've upgraded, the PSP re-rooted itself into the memory stick. So it's looking for a folder that doesn't exist. (But that's just what I think...) I've had this problem also. After you format it with the PSP, it should work fine. As for your game files, they should still be saved on the memory stick. Search all your files with your computer then save them to your computer so they don't get formatted. After the format, put the files back onto the memory stick where they belong and everything should work fine! Please ask if you have any questions!

Try save your important data on memory stick and give it a format.