SYMPTOMS
When a DHCP database becomes corrupted, it may be necessary to rebuild the
database from the registry.
For additional information, please see the following article in the
Microsoft Knowledge Base:
ARTICLE-ID: 173396
TITLE : How to Restore a Corrupted DHCP Database File
After doing the reconcile, when you view the properties for a client lease,
the computer name will be listed as the IP address of the lease and an
arbitrary hexadecimal value will be listed as the client identifier. These
will be replaced with the appropriate information as the clients renew
their leases.
You will also notice that reservations now have a lease expiration.
Normally, reservations should have "Infinite" for Lease Expires: under
Client Properties (or N/A if the client has never actually leased the
reserved IP address).
The lease expiration date will also be reseated back to Infinite when the
client renews its IP address.
There is one scenario when this does not happen.
If you go to Active Leases, double-click the reservation and select OK to
exit, the following message will be displayed:
The Unique Identifier you have entered may not be correct. Do you want
to use this Identifier anyway?
If you select Yes, the client will NOT get its reserved IP address. Instead
it will get the next available IP address from the scope.
To prevent clients from recieving IP addresses before the DHCP server completes the reconciliation process, you must take the DHCP server off the network prior to rebuilding the database. If you leave the DHCP server on the network, this behavior may occur.
RESOLUTION
This problem can be fixed by going back to the reservation before the
client renews and replacing the arbitrary hexadecimal value listed as the
client Unique Identifier with the media access control address for the
client.
If you try to change the hexadecimal value after the client has already
renewed and received a different IP address, you will get the following
error:
An error occurred while accessing the DHCP database; look at the DHCP
server event log for more information
You will also receive the following message in Event Viewer:
Event ID : 1014
Source : JET
Description: The JET Database call returned the following Error: -1605.
This happens because the client media access control address is already in
the database.
At this point, you can release the IP address from the client side
(Ipconfig.exe /RELEASE on Windows NT or Winipcfg.exe and select Release on
Windows 95), and enter the media access control address to the reservation
again. The client will be able to lease its reservation now.