look i have firefox 3.1 the newest version and i can install add ons but something strange happend...this keeps poping out when i try to install a add on ore a theme...

Firefox could not install the file at

https://addons.mozilla.org/en-US/firefox/downloads/file/30505/bugmenot-2.0-fx.xpi

because: Unexpected installation error
Review the Error Console log for more details.
-203



Help!