You can tell by the DHCP server log when a computer is disconnected from the network? Thank you.

You can use DHCP server events tool. If you have already upgraded to Windows server 2008 R2.http://blogs.technet.com/teamdhcp/archive/2009/03/20/tool-to-read-dhcp-server-events-for-windows-server-2008-r2.aspxhttp://www.windowsecurity.com/articles/DHCP-Security-Part2.htmlThankshttp://technetfaqs.wordpress.com

Is Windows 2003 R2

Hi, You can check the DHCP log: http://technet.microsoft.com/en-us/library/cc776384(WS.10).aspx Hope it helps. Tim Quan - MSFT