Firefox user changed...I need urgent help!!

[Filliz]

When that happens (the thing pops up saying account is in use) just click exit/close/canel/whatever it says (firefox then closes) and reopen firefox...it will work fine teh second time.

Nope.
That didn't work for me.
Tried it a couple of times before I decided to reboot

[tesco]

Nope.
That didn't work for me.
Tried it a couple of times before I decided to reboot

works for me.
although i haven't had it in a while, maybe i'm forgetting something...
maybe you have to close a firefox.exe process in task manager.