I was wrong! The fix only lasted a short time after deleting cookies.sqlite. I'm not sure but it probably only lasts until the next reboot of Firefox. I haven't established that yet as it means a few cycles of deleting, signing on, rebooting and retesting and it's not actually stopping the PC working, it's just a nuisance. I think, in my case it may have happened after the recent update to Firefox 3.08. Certainly the Mozilla forum has quite a few complaints about this happening but apart from deleting the cookies.sqlite file and checking for finger trouble in the configuration, no other suggestions. And while some of the correspondents suggest it might coincide with an update, it could be for any update to Firefox 3 not just 3.08. The problem also seems to occur with Firefox 2 so I am at a loss.
Has anyone else had this problem or have any suggestions I could try. I have run Malwarebytes, Spybot S & D and AVG 8.5 is fully updated and running which hopefully rules out a nasty. The next step is probably a full reinstall of Firefox but I know you can come unstuck with not removing all the old software to start with so not just yet.
Has any helpful Kitizen got the solution, please?
Tony