Corrupted Data Fix!
Load the game up like usual (without the proxy and with the patch). Go to split screen and load the Prestige file (not the error file) and start a game. Kill yourself by cooking a grenade and end the game after you respawn. Next load up the error file and quit the game. Start the proxy and delete the patch and there you go! You will no longer receive the corrupted data error. I have tried this almost 10 times now and it has worked every time.
If you want prestige 7 then use the file below. You will need to do the data trick to get it to work. Some people prefer the prestige 7 symbol so I thought I should upload it if you're one of them
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For the prestige 7 file just copy the folder to PS3 > SAVEDATA and overwrite.
A little hint on how to get all 10 prestige titles and emblem on a lower prestige:
First go to prestige 10 and play on it until you get to the 2nd ranking. Do the hack and change the file to whatever prestige you want and BAM all 10 titles and emblems ^^
To get all 10 custom classes on a lower level prestige:
Got to prestige 10 and play until you get to the 4th rank. Do the hack and change to to whatever prestige you want and when you get to the 4th level on that prestige again, you will have all 10 custom classes unlocked!
If anyone needs help or is just too lazy to do this then throw me a message and I will update your account with whatever prestige you want.
FAQ: (To help some of you out)
Do I still get all previous prestige titles/emblems if I go to prestige x?
Yes you do once you hit level level 2.
Do I still get all custom classes I would normally get in prestige x?
Yes once you hit level 4.
Does any of my stats (k/s, headshots, k/d and so on) get messed up?
No. The good thing about this hack is it won't give you outrageous stats (52288654 kills, 324532566 deaths - you get what I'm saying) like what most prestige hacks do. This is how most of those hackers got banned

You will get to keep your current stats.
PSN signs out before I can even finish the hack. Any way to delay the time out?
Unfortunately, no. The only thing you can do is click your ass off once you enter the replace file URLs. If you mess up then remove all those URLs, sign in then add the URLs again before you start the game. You don't even need to stop/start the proxy if you made a booboo!