VISTA SP1, COMODO and Sonicwall VPN

We have a sonicwall VPN gateway on a remote site.
On my PC I run the very latest COMODO (free) firewall and the SonicWall Global VPN Client.
Two days ago I updated my Vista to SP1 (Yes I know very silly), but the only problem I now have is my SonicWall VPN Client no longer works.
If I stop COMODO it works.
I have uninstalled / reinstalled both COMODO and SonicWall Global VPN Client - but I still can’t get it to work.
Has any one else had this problem??
And has any one else solved this problem!!
Many, many thanks in advance,
Kindest regards,