can connect to internet through LAN but cannot ping external ip's!

[no2broady]

I know that there is a similar post to this under the title of:
Can ping network connections but cannot access internet
This situation is slightly differnt though.

I have already posted this under the VPN area of the page but it has more relavence here.

Basically I'm running a 40 pc network, and one W2K server.

I have been trying to set up some of these machines to access a VPN. When i try to connect through the network it throws back an unable to connect error. I have tried to ping the VPN with no luck, in fact i cannot ping any external IP address or name from within the network.

Most of these client PC's are using the internet from the Proxy service. There are no problems here, DHCP is enabled, and i have fixed a test machines IP address with no luck.

I'm also running ISA server but have this correctly configured, i can ping and connect to the VPN from the ISA Server.

I have been looking into other way's to configure the Local Area connection and have tried setting it up to point to our router but again still no joy.

Any help would be most appreciated.

JB

 

[dearingkr]

More details on the network setup would be helpful.

Is the ISA server the local default gateway?
If not, then you have a routing issue.

If routing is good, then I believe your ISA config may be the problem.

You said the PCs use ISA as the proxy. That will only work for web pages (port 80).

Do you have a protocol rule allowing ICMP?

VPN requires TCP port 1720 and protocol 47 (GRE).

MCSE CCNA CCDA