Hello everyone.Couple days ago we found an interest problem.Windows vista pc's refused to receive IP addresses from DHCP server.I setted up port mirroring on a switch and captured some packets - standard broadcast request, and reply from a server with address offering.But pc still cannot get an address. In status of a network connection I can see that pc is only sending packets, and not receiving it.Ive checked everything - from drivers to switches - everything is working, and pc with windows XP are still able to get IP address.We found the reason. It was DHCP server 033 option - static route. One of our administrators added one new route to a server couple days ago. After I removed it - vista pc accepted IP address in 5 seconds.So, I have a question - is there any restriction for DHCP packets in vista? Because XP pc's work great all the time.

Hi, The DHCP server may not support DHCP BROADCAST flag. The following KB article has explained this situation. Windows Vista cannot obtain an IP address from certain routers or from certain non-Microsoft DHCP servers http://support.microsoft.com/kb/928233 The following blog may be also helpful on this. http://blogs.technet.com/teamdhcp/archive/2006/11/08/use-of-broadcast-b-flag-in-dhcp.aspx Hope it helps.

hello,i don't think, that this is dhcp server issue - we have one DHCP based on windows 2003 and second on windows 2008 server.the point is, that OS other than windows vista home basic\premium getting their ip addresses without any problems!i have two similar laptops - one with vista home and second with vista business, and business is working!so, i can only suppose, that home version had some restriction in tcp\ip protocol...

Hi, It seems that this behavior is not related to the guest computers. I suggest that you post a new thread to our Windows Server 2003/2008 forum to focus on the DHCP: 033 Static Route Option related questions. http://social.technet.microsoft.com/Forums/en-US/winservermanager/threads/ Hope we will get an answer soon.

ok, I wrote a crosspost to that forum, but it seems that no one is looking that forums )do somebody know any debug mode for DHCP client? it really interest to look, what is happening in a system.

Hi, How does it work? Is there any discuss in your new thread in the Windows Server forum?

nope...no one even replied.i found this blog - http://blogs.technet.com/teamdhcp/i'll try to write them a letter, and post here their reply.

problem solved, but not the way it should )I removed most of static routes and added option 121 Classless static routes - using that option we can add routes and define mask.

Hi, Thank you for your information. I will share this with our tech guys in Windows Server forum.