In a Windows 2000 domain, DHCP servers must be authorized in the Active Directory before they can service DHCP clients. The forest wide limit is approximately 850 DHCP servers. When the limit is reached, you receive:
Administration limit for this request has exceeded.
To resolve the issue:
1. Upgrade every DHCP server to Windows 2000 Service Pack 2 or later. You must also upgrade any server that is used to administer DHCP.
2. On every DHCP server, and on any server that is used to administer DHCP, use Regedt32 to Add Value name SP2Mode, a REG_DWORD data type, at HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\DHCPServer\Parameters.
3. Set the SP2Mode data value to 1.
NOTE: If you uninstall SP2, a DHCP Server may stop servicing clients.