If you close Firefox, then start Firefox in Safe Mode, does the problem still occur? For instructions on starting in Safe Mode, see Diagnose Firefox issues using Troubleshoot Mode.

The first time I used Safe there was an improvement. I have tried several times since and phenomena still there so first time was probably a fluke. Thanks for the ref to Safe. Never knew about that.

You should do a cleanup and remove the old Java Console extensions (Tools > Add-ons > Extensions).

See: http://forums.mozillazine.org/viewtopic.php?f=38&t=1708795 - Java Console extensions http://forums.mozillazine.org/viewtopic.php?f=38&t=1710075 - Upgrade to FF 3.6 added many Java Console addons --- Make sure that Norton isn't blocking anything. See Configure firewalls so that Firefox can access the Internet and http://kb.mozillazine.org/Firewalls

Thanks. Did clean out the Java extensions but no improvement. As "Bluefang" said in one of your references, the Java extensions have no effect on Firefox Java functionality. They are only useful for Java developers. And Norton isn't blocking anything.

You can create a new profile as a test to check if your current profile is causing the problems. See [[Basic Troubleshooting|#Make_a_new_profile|Basic Troubleshooting:Make a new profile]]

There may be extensions installed by default in a new profile, so check that in "Tools > Add-ons > Extensions".

If that new profile works then you can transfer some files from the old profile to that new profile (be careful not to copy corrupted files). See http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Can you check your Windows Firewall settings? It's possible that it's routing Firefox requests differently. At least one other Firefox user has reported that his Windows Firewall was set to block Firefox 3.6.

Thanks, but Windows Firewall has always been Off.