Can't start Packet Filtering

[IainRR]

Hi there

We have Proxy V2.0 running on a W2K SP3 server. I've set up the internal and external network cards etc but as yet not actually connected a cable to the external interface.
When I try to go set up Packet Filtering via Proxy Service Properties | Security I get the following message -

Packet filtering cannot be enabled on this server because it does not have an external network interface.

Do I need to have an actual connection to a gateway router for this setup page to be available ??

thanks
Iain Rhodes
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