I upgraded to Extreme Security (3 computer license). It installed fine on 2 of the 3, but on the 3rd, I get a blank screen with zonealarm logo in header. I THINK it might be a scan (why I think that later) but obviously can't tell. I can open the control center and it says everything is installed and running. However when I click on antivirus/antispyware, I get a blank panel - nothing loads in it. I can run update and that pulls down fine. If I click on Scan Now, I get the same blank window I get on startup (why I think the startup one is a scan). The only thing "Extreme" about this is how slow the computer is now running - not sure if it is related to the non-proper functioning or not.
I've uninstalled/installed several times to no avail - including the "clean" version suggested. Any help will be greatly appreciated.