Firefox 3.5.1 process freezes when opening Zimbra webmail

[DougWare]

I'm the administrator, but this is a user problem....so here we go.

We have a new client workstation. When the user tries to open the Zimbra web client in Firefox 3.5.1, the entire Firefox process freezes and has to be terminated using Task Manager. This happens every time...

When the user tries to visit the site, they are redirected to the SSL site, the certificate warning pops up (with no option to import, save, ignore, you can only view the cert or close). If you click view or close, the entire Firefox process hangs.

I exported our Zimbra's CA certificate and imported it into Firefox. Now the warning doesn't appear, the Firefox process just hangs.

The above process and result are the same, even when running Firefox as an user with administrative privileges.

It works fine in IE....

Workstation Details:
OS: Vista Business 32-bit
Browsers: IE 8, Firefox 3.5.1
Antivirus: Avast

Any ideas where to go from here?

[DougWare]

Manually installing the certificates fixed the freezing, however we are still seeing weird behavior on some of our clients.

One user can still access her mailbox fine from her old 32-bit/XP laptop without a problem, but from her new 64-bit/Vista system, straight things happen such as slowness, the folders panel never populates, etc.

We have several users we are seeing this problem with.

[phoenix]

Originally Posted by DougWare

Antivirus: Avast

Any ideas where to go from here?

I'd suggest you disable or remove the A/V (see if it's set to check any email), It's quite likely to be causing the problems. If it's not that check to see if you have any incompatible extensions, create a new (additional) user profile in FF and see if that fixes the problem. FWIW, I don't have any problem accessing the Zimbra Web UI with FF3.5.x on Windows XP, Vista or 7. The your problem happens would lead me to think it's a problem with your A/V software.

[DougWare]

I don't believe it's our AV software, everyone is running the same version of Avast with the same settings.