I have changed from demand dial ISDN to leased line for Internet/Email connection. I think I have configured everything correctly but I can't seem to allow VPN clients in (I get a message on the client about the server not responding). The server is running SBS2000 with two NIC's. Also all Win9x clients on the network get an error message about no domain controller available at login but all the W2K clients login fine !
What errors do you see in the Event Log? The configuration is very specific for SBS, as you're running all services on the same machine, which is also a DC. Did you use the procedures for DNS installation as shown in the article on running ISA Server on a DC over at www.isaserver.org/shinder?
So everything works OK with Win2k clients but not with 9x clients? If so, make sure that there are no "hard coded" DNS/WINS server addresses on the 9x clients, as those will override anything the ISA/VPN server delivers to them. You might need to create an LMHOSTS file to help them log on.
There is no hard coding all WINS/DNS info is from the DHCP server. If I ignore the message about not being able to login to the domain the Win9x clients are able to ping other PC's and the server by name. You can see why I am confused !