Last updated January 19, 2001

XCLN: How to Fully Remove the Windows 95 and Windows NT Clients [Q165961]

PSS ID Number: Q165961
Article last modified on 04-19-1999

The information in this article applies to:
- Microsoft Exchange Windows NT client, version 4.0
- Microsoft Exchange Windows 95/98 client, version 4.0

IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information on how to do this, view the "Restoring the Registry" online Help topic in Regedit.exe or the "Restoring a Registry Key" online Help topic in Regedt32.exe.

SYMPTOMS
When you attempt to remove Microsoft Exchange Client by clicking the 'Add/Remove' in 'Control Panel' or clicking 'Add/Remove' in Exchange Client Setup, Exchange Client does not seem to be removed.

CAUSE
Several registry keys and files remain.

WORKAROUND
To remove Microsoft Exchange Windows 95 and Windows NT clients from a computer that does not also have Microsoft Exchange Server installed on it, follow these steps:

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall Windows. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.
For information about how to edit the registry, view the "Changing Keys And Values" online Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" online Help topics in Regedt32.exe. Note that you should back up the registry before you edit it.

  1. If you plan to reinstall the client later, synchronize any .ost files, and back up any .pst and .pab files. (This assumes there is no corruption in the files.) NOTE: Backing up '.OST'-files will not work. That information will NOT be recoverable! Only a synchronization with the Exchange Server Mailbox will ensure there is no loss of information.
  2. Log out of any applications.
  3. Back up the entire client computer. (Later, registry keys will be removed. Full backup is required unless recovery does not matter.)
  4. In Control Panel, click Add/Remove Software. Remove any Exchange and messaging options.
  5. Go to the latest exchange Setup and click Remove All. ("Latest" Setup means the highest version installed on this computer.)
  6. Start Registry Editor.
  7. Go to the following key in the registry:
    HKEY_LOCAL_ MACHINE\Software\Microsoft...
  8. Delete the Exchange and Windows Messaging folders and subkeys.
  9. Exit Registry Editor.
  10. Do a search on *exch* and remove all remaining files.
  11. Remove the '.\windows\system32\Msremind.wav'-file.
  12. Restart the computer.
To re-install Exchange Client:
  1. Rename the Mapi.dll, Mapi32.dll, and Mfcans32.dll to *.old. These files are usually located in the '.\windows\system32\'-directory.
  2. Restart the computer.
  3. Reinstall Exchange Client.
  4. You can point the client to the "old" '.PAB'- and '.PST'-files. However, if you are reinstalling due to corruption issues, it's best to test the client with new files. Then, import the old information into the new files. ( On the [File]-menu, click [Import], and then click '.pab' and so on.)
  5. If all is OK, remove the Mapi.old and Mapi32.old files (renamed in the step 1 above).
To remove a Microsoft Exchange Windows NT client from a computer that also has Microsoft Exchange Server installed, follow these steps:
  1. In 'Control Panel' 'Services', stop 'System Attendant'.
  2. In 'Control Panel' 'Add/Remove Programs', select 'Microsoft Exchange' and then click [Add/Remove].
  3. Click 'Remove All'.
  4. When asked if you want to remove all shared components, click [KEEP].
  5. Once Setup is done, rename the Exchange directory where Exchange Client was installed.
  6. Start Registry Editor . Export the the following keys and then delete them: NOTE: Make sure you export the keys prior to deleting them, in case of error.
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Client
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Forms Registry
    Delete the following String Value:
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Exchange Provider
    "Rpc_Binding_Order"
  7. Restart the computer.
To reinstall Exchange Client on the computer running Exchange Server:
  1. In Control Panel Services, stop System Attendant.
  2. Reinstall Exchange Client.
  3. Restart computer and make sure all Exchange Server Services and the Exchange Client function properly.
Copyright Microsoft Corporation 1999.