Thanks TT, the link gets close but because of its age certain recommendations may be inaccurate. I've got all the permissions enabled in Zone Alarm, but still get the problem. It seems to have been around for a long time.
Beg your pardon TT, my eye didn't catch it, but I did try all the suggestions which applied. In fact, only one did apply and that was to allow all the permissions for Firefox to access the net. I'll try the last recommendation. Thanks.