I have been watching this thread with interest but have refrained from posting any offer of help because Lucy posted exactly what needs to be done to solve the problem.
However, if I may, as an experienced phpBB user, I'd like to offer an explanation for the reason behind the problem, because a few people appear to have criticised the forum software and the CarersUK team for "cocking things up".
As has been said elsewhere on the forum, the reason the forum software was upgraded was because there was an upgrade release issued. Why upgrade? Because it protects YOU and your beloved forum from hackers and spammers. Over time, hackers manage to develop ways to infiltrate the code the forum software uses, finding loopholes in the code to exploit. When these loopholes are discovered, updates are provided for protection against such exploits. Therefore it is imperative that forum software upgrades are performed.
A side effect of such major upgrades can affect users (members) if there is a) a change in log-in storage details (cookies) or b) there is a change in the way cookies are handled. Cookies are not the chocolate chip variety you eat but a computer term used to describe the storage, on your own machine, of information pertaining to a particular website or web page for easy reference/access for when returning to the same website/web page. For this reason, clearing your cookies (and sometimes your cache too) will solve the problem.
I can confirm that this forum software IS compatible with Firefox (Direpox LOL) and in fact all other major browsers so there is NOTHING wrong with the forum software, the forum or the upgrade. The problem rests with YOU, the member, if you ARE having problems of course.
Please follow Lucy's instructions in the OP and in particular, the link to the WikiHow for clearing browsers cookies (for Firefox - http://www.wikihow.com/Clear-Your-Brows ... es#Firefox
) But before you attempt to clear your cookies, please remember to CLOSE any open web pages, especially CarersUK, first.
If you are STILL having problems then I recommend that you download and install a program called CCleaner (otherwise known, seriously, as Crap Cleaner) http://www.piriform.com/ccleaner/download/standard
and run it. It will not only clean out your, erm... crap (including cookies, cache) but make your computer run a bit faster (because it has cleaned out the erm.... crap!)
If anyone has problems with CCleaner and wishes to try it and use it to it's full potential, let me know and maybe I'll write a tutorial for it, including screenshots to guide you.
I said Maybe!