Free Candy For Everyone

I’ve been having a majorly annoying Wordpress theme problem for months now where every few days my theme resets back to the default Wordpress theme. I’ve searched the web for why this is happening, I’ve tried removing all plugins, I’ve tried using different themes, but most themes I try it just happens again and again. I’m totally at a loss and getting to my wits end on this. Anyone out there know anything about this? I’m using the newest version of Wordpress - 2.6.1 - it’s supposed to be fixed as of 2.4 or something like that!