LiveUpdate prevents links from working

Using Norton Internet Security 2012, Windows vista, Thunderbird 13.0.1, Mozilla Firefox 13.0.1

After a Liveupdate, all links in Thunderbird emails and any other program including Norton do not work.

Click on link and nothing happens.

It is as if my computer suddenly does not know who my default open browser is.

I can fix this by closing Firefox and reopening and then restoring session.

This issue started 2012-05-08.

 

It does not occur for every update check.

But actual Update received at 15:13:02  Today 2012-08-07  (UK = 07-08-2012) which caused the issue.

Updated:

norton pulse Updates

Norton Activity Map data

Norton 2012 Reputation Revocation list.

 

Has anyone heard of this?