I'been using Ubuntu for more than a year now, and upgraded to 8.10 in November 2008. I use Filezilla to maintain my website, but suddenly I cannot upload - every attempt times out and never delivers files. Other FTP programs do the same (including the Javascript for Fotopic). At the same time, Evolution started prompting me for the POP password each day, though the option to remember heh password is ticked.
I have a horrible suspicion that I shall have to reinstall 8.10 with all that entails in re-entering details. Anyone had this experience?

Do you mean you can't use ftp at all or only to certain ftp sites? Does Filezilla keep your userid & password or do you enter it anew each time you connect to your remote website? If the latter then why not try deleting and reentering the ftp site. Maybe only your id+password got lost and there's no need to reinstall your whole OS.
Cheers,
jdk

Can't use it at all - tried re-entering user, host, all to no effect, and no form of FTP works to any site.

Looks like FTP is filtered on your network. Do you use proxy for web browsing? Have you tried specifying it for FTP too?

No proxy used. Windows machine on same router has no problems with FTP. Baffling!