DOCUMENT:Q180002  28-MAR-1999  [exchange]
TITLE   :XADM: Error Message: Hotfix Already Installed
PRODUCT :Microsoft Exchange
PROD/VER:WINDOWS:4.0,5.0,5.5
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 
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SYMPTOMS
========

When you attempt to install a hotfix that has previously been installed, you may
receive the following error message:

   Hotfix already installed.

CAUSE
=====

The Hotfix program checks the HOTFIX key in the registry to determine if the
hotfix being applied has already been installed.

This error occurs if the POST-SPx hotfix was not specifically removed prior to
reapplying the service pack.

WORKAROUND
==========

When you apply a hotfix using the hotfix program, it adds a registry value to
the Windows NT registry to indicate that it has been applied. This value may be
removed using the registry editor for Microsoft Windows NT. The following
procedure can be used to remove this value and reapplying hotfixes.

WARNING: Using Registry Editor incorrectly can cause serious, system-wide
problems that may require you to reinstall Windows NT to correct them. Microsoft
cannot guarantee that any problems resulting from the use of Registry Editor can
be solved. Use this tool at your own risk.

1. Run Registry Editor (Regedt32.exe).

2. From the HKEY_LOCAL_MACHINE subtree, go to the following key:

      \SOFTWARE\Microsoft\Windows NT\CurrentVersion\HOTFIX

3. Select the HOTFIX key and press the Delete (Del) key on the keyboard or click
   Delete on the Edit menu.

4. Reinstall all applicable hotfixes.

Additional query words: Post spx sp4 /i /r

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Keywords          :  
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : WINDOWS:4.0,5.0,5.5
Issue type        : kbprb

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