We recently ran into this problem wherein the DHCP MMC started throwing errors anytime we try to launch it. After a good length of troubleshooting, we found that the number of reservations on the DHCP were 87. Sounds crazy???
Yes, its true. Microsoft is aware of this issue and have published a workaround, released a hotfix and have fixed it in Windows Server 2003 SP2. All the details are here in this Microsoft KB article 902954.
The errors were
Snap-in Failed to Initialize
when trying to view the scope reservations
The DHCP server you specified cannot be located. The DHCP server might be down, there might be network problems, or the DHCP service might not be installed. The error was: The parameter is incorrect.
When trying to connect to the DHCP server.
The workaround is simply to add a reservation to the scope so it is not 87 reservations anymore or if you had 87 scopes on the DHCP server then add another scope to escape 87 again.
The commands are
Add another reservation
netsh dhcp server ServerIP scope ScopeIP add reservedip ReservedIP MACAddress ClientName
Add another scope
netsh dhcp server ServerIP add scope ScopeIPSubnetMask ScopeName ScopeComment
As said earlier, there is a HOTFIX and is also fixed in Windows Server 2003 SP2. Click here for details.