[TomGuy]

Uninstall 3.1 and reinstall 3.0.

See if that works.

[I have had to return to previous versions before.]

[Number57]

3.0 did the same thing. Had to download 2.0.0.16 before it starting working again. WTF.

Lost all my bookmarks :/

[reg45]

There is no Firefox version 3.1 (except for a possible unstable beta). Version 3.0.1 is the latest stable release. 3.0.1 would be a bug-fix version of 3.0.

BTW: I'm using 3.0.1 without any significant problems - except for sites that are written with IE specific code.