I don't know if anybody else had this problem but whenever I opened PS it wouldn't save my preferences for the next time, so basically I couldn't use brushes because once I loaded them, they would dissappear as soon as I closed PS. It would come up with a message like this. "Could not save preferences because the file is locked or you do not have necessary privileges".

If this is happening to you and you need help, the 2nd solution here worked for me, so just if anybody needs it. Hope this helps somebody.

http://kb2.adobe.com/cps/845/cpsid_84517.html