As far as I know the ZMS client on Windows working only with version 2.1 By changing the OUTPUT default policy on my firewall to ACCEPT, I was able to connect from my ZMS client (actually I could've achieved the same thing by leaving it at DROP but by inserting an "accept established" rule in the OUTPUT chain, right? And shouldn't that be the default?). But immediately after successful authentication, I received the error "Request: missing or invalid type", and my ZMS client quit. Thoughts? Thanks, Mick Bauer