Using DHCPCMD to Modify a Reservation Converts It to a Lease

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When you use the DHCPCMD command ADDRESERVEDIP to modify an existingreservation, error 20022 (ERROR_DHCP_RESERVEDIP_EXISTS) is returned. Whenyou subsequently inspect the reservation using DHCP ADMIN, the reservationhas been turned into an active lease. If DHCPCMD is run again to modify thelease, it works correctly and is turned back into a reservation.
This is a problem in DHCP server, which incorrectly handles themodification of an existing reservation, causing the reservation to bepartially deleted. This results in the remaining data looking like anactive lease.

Running the same command again causes the reservation to be correctly re-added.
To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:
For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:
Microsoft has confirmed this to be a problem in Windows NT version 4.0. This problem was first corrected in Windows NT version 4.0 Service Pack 5.
4.00 dhcpadmn tcpip

Article ID: 198541 - Last Review: 01/07/2015 07:50:13 - Revision: 3.0

Microsoft Windows NT Server 4.0 Standard Edition, Microsoft Windows NT Server 4.0 Enterprise Edition

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