It could be that the Windows 7 computers boot up faster and the switch you are connecting to is not ready by the time the PC is making its DHCP request. This can happen if you are using Cisco switches that are set up to run a spanning tree test every time a new connection is made to a port. Google (or Bing) "spantree portfast dhcp" for a bunch of info or read this Cisco document:
http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_note 09186a00800b1500.shtml Tom From: Eisenberg, Wayne [mailto:wayne.eisenb...@pbvllc.com] Sent: Thursday, January 14, 2010 7:20 PM To: NT System Admin Issues Subject: Windows 7 and DHCP puzzler Has anyone noticed any problems with Windows 7 getting an IP address from DHCP? In our pilot testing, we are noticing that a significant portion (>30%) of our users are not successfully getting an IP address from the local DHCP server. It happens with wired and/or wireless, across make and model, different antivirus programs. It can happen if the DHCP server is on the same subnet and also if it is on a different subnet (ip helper address configured in the router). No firewalls turned on. Everything was fine for a while, and then some laptop users started having problems getting an address from their home router. Some folks can get an address at home, but have trouble getting it at the office. If you give them a static IP, they can work. That is obviously not a viable solution. We need DHCP to work no matter where they are - just like it works for XP. :) BTW, none of our XP users have any problems at all. This is strictly a Win7 issue. We've tried removing some MS patches among other things, but nothing fixes it across the board. Any ideas? Points and ice cream will be awarded to anyone who can come up with an answer. :) Thanks, Wayne ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~
