Apply this hotfix for dropped DHCP reservations

If your IP address reservations are mysteriously dropped by your DHCP server, check if you have Windows Server 2008 R2. There's a known bùg that can cause this Windows version to delete DHCP reservations when it shouldn't. One possible symptom of this problem is routers crashing after you've recently upgraded your Windows Server to 2008 R2. Fortunately, there's a hotfix for this problem. You can download it at the following address: http://support.microsoft.com/kb/981776