I'd recommend everyone backup their profile often. This goes especially if you visit any modded servers. Some people lose their rank, some lose BK tags and some lose all their custom settings. In my case I have to
put my profile back in. I had at one time backed it up to a temp file but my operating system went down and I lost 3 weeks of data and this was when I was playing 18 hours a day. So since then I backup to a DVD.
Having prestiged 10 times I know what it is like to start over but you do not want to start over from scratch so take a few minutes and put the app data profile onto a DVD or CD.

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