http://www.dslreports.com/forum/r18328013-DHCP-Problems-With-Cisco-871
...for your DHCP reservation, do a sh ip dhcp binding. Find your DHCP lease and look at the Client-ID. If you find your mac address prepended by a 01, or something else, remove the hardware-address setting under your reservation and replace it with client-identifier and the address found under sh ip dhcp binding. Then do a clear ip dhcp bind *, and do a release and renew on your PC...
