trouble starting VNC behind ZoneAlarm

Jerry Riechert JerryR "at"
Wed Apr 7 16:12:00 2004

-----Original Message-----
From: vnc-list-admin "at" [mailto:vnc-list-admin "at"] On
Behalf Of Gary Sieker
Sent: Tuesday, April 06, 2004 12:45 PM
To: vnc-list "at"
Subject: trouble starting VNC behind ZoneAlarm

>My home PC runs XP Pro SP1 with the latest ZoneAlarm free version. It's

>also behind a D-link DI-604 router although I don't think that's the 
>problem. To connect to my work PC I first start VPN. Once connected I 
>then start VNC viewer. But I never get the password prompt from work PC

>unless I change ZA settings to no protection. Once VNC starts I can set

>ZA back to high protection and it continues to work fine. I can also 
>disconnect and restart the viewer in the same VPN session and it works 
>OK. Is there some setting I need in ZA so that I don't have to change 
>the protection settings?

Hi Jerry.

I've had similar problems with trying to use VNC thru a vpn with ZA
running on my PC at home.  What I think I finally did was add both the
external ip address of my work firewall and the internal address of my
work pc to the 'local' ip list in ZA.  I believe this cured the problem
(although I'm not really sure why...)  Since you're behind a router,
this isn't an additional security risk as long as you've got your router
buttoned down.  If you were running ZA alone, with 
no router, then I would be a little more hesitant to do this...

-------Original Message-------

I already have my work PC and the VPN portal in my tursted zone in
ZoneAlarm. In playing with it yesterday I determined that I only have to
drop the ZA internet security from High to Medium for the VNC connection
to work. Once logged in I can set it back to High. I also have checked
the advanced setting to allow uncommon protocols (I think that's what it
is), a suggestion I saw somewhere.