I was a Two Star Gen and now all of my rank in multiplayer is gone. Does anyone know how to reversse this? I have know idea who to contact. I know it's all on servers. Thanks.

Nope there is NO possible way of getting it back, unless you made a copy.But then again you wouldn't be here if you had that. Sorry to say m8, you're outa luck.

Your serial is connected to your rank and sometimes if something happens where the game thinks your save data gets corrupted, the game will make a .bak file of it. It's usually called 'mpdata.bak'. This is your old file with rank.

You could try renaming the file back to mpdata and your serial has to be in the game. I know some people reinstall Windows or something and just load up WaW and it still works.