XADM: Cannot Apply Service Pack on Key Management Server (235418)

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you attempt to apply a Microsoft Exchange Server 5.5 service pack on a Key Management (KM) server, the following error message may be displayed when the Update.exe program attempts to determine which version of the Kmserver.exe file is installed on the computer:

The system cannot find the file specified.

CAUSE

This problem can occur when the KM server password has been added to the ImagePath registry value under the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeKMS

WORKAROUND

Remove the KM server password from the ImagePath registry value. To do so, use the following steps.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

Start Registry Editor (Regedt32.exe).
Locate the ImagePath value under the following key in the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeKMS
On the Edit menu, click String, remove the KM server password, and then click OK. When you are finished modifying the value, it should contain the full path to Kmserver.exe file only. By default, the value is set to C:\Exchsrvr\Bin\Kmserver.exe.
Quit Registry Editor.