Can't connect to Zimbra with Firefox

[chh]

Hi,

I have a strange problem.
I have a Notebook (Win XP) that I use both at work and at home.
Using this Notebook and Firefox I get this results when connecting to Zimbra:

Work: Timeout
Home: Timeout
Home with VPN up: Timeout
random other external network: works fine

At home without VPN and at other networks I use a dyndns address and portforwarding.
With VPN I use the internal IP.

Both at home and at work I can ping the server and I can connect to Zimbra using Opera.

One thing that might have to do with it.
At work we have 3 class B networks that are connected via a router:
10.1.0.0
10.10.0.0
10.100.0.0
Server and Laptop are in the 10.10.0.0 subnet.

At home I have a 10.1.1.0 class C network, so any IP I have at home are valid at work.

Interestingly I have the same issue with my PC at home (Linux), Firefox not connecting, Opera works.

Any ideas why this does not work??

Thanks

Christian

[uxbod]

What version of FF ? Have you tried both 2 and 3RC1 ?

[chh]

At home the Version is 2.0.0.14. On my notebook it should be as well.
I did not try the RC1 yet only some of the betas at home, but I downgraded again. (never used the beta to connect to Zimbra though).
Strange thing is that it works with the FF on the notebook when in another network.

[Bill Brock]

You don't have FF set to use a proxy server by any chance?

[uxbod]

Good point Bill ... Have you also cleared your FF cache ? What if you attempt to connect to ZCS via its IP address ?

[chh]

So it is halfway solved, on my notebook I added a proxy, and after removing it it works again (stupid me).
But although an zupgrade to FF3rc1 "solved" the problem at home as well, I wonder why it did not work before, there was never a proxy added to FF at home.