I experience some strange issues with DHCP in Vista. I want to install a PC with Vista behind a firewall. The router is a Fedora Core5 machine with default DHCP server running. The network has a privat IP range (172.16.x.x). There is no direct network connection to the outside world apart from web connection through a proxy. I noticed, that if I install Vista, the Vista machine does not get a IP address from the DHCP server. If I installed Vista on the same hardware in a public IP network, also with FC5 DHCP server, Vista did accept an IP address. If in the private network I opened the firewall by configuring NAT, I noticed that Vista does accepted an IP address. Futhermore I noticed that I can reproduce this on other harware. Also XP clients and linux clients don't have any problems getting DHCP addresses from the server. The server log from the DHCP server shows, that if Vista does not accept an IP address, there is a DHCPDISCOVER and a DHCPOFFER, but no DHCPREQUEST and DHCPACK as there should be. It looks like Vista gets a DHCP address offered but refuses it. What is wrong here and how can I solve this problem.

hi, THis is sounds strange for us and interested in debugging/resolving this: It would be great if you send us the NETMON or wiresharkcapture to us. You can send those trace files to ftdhcp@microsoft.com. Thanks