MAPI solutions do not work because Outlook.exe is not properly registered under the \App Paths key in the Registry

Applies to: Microsoft Outlook 2010Microsoft Office Outlook 2007

Symptoms

If you are using a custom MAPI solution (for example, an Outlook add-in), the solution may not work because Outlook.exe is not properly registered in the Windows registry.

Note, the actual problem you experience with the custom solution depends on how it uses the Outlook.exe registration information.

Cause

This problem can occur if Outlook.exe is not registered correctly under the following keys in the Windows registry:
  • 32-bit versions of Windows

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths
  • 64-bit versions of Windows

    HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\App Paths
If Outlook.exe is properly registered, you will find an \Outlook.exe subkey under the above key, and under the \Outlook.exe subkey you will find a string value called Path whose data references the correct path to Outlook.exe on your computer. The following figure shows the correct Outlook.exe registration on a 32-bit version of Windows.

The screen shot for the Outlook.exe registration


NOTE: The path to Outlook.exe on your computer may vary from the above figure if you installed Office in a non-default location.

Resolution

To resolve this problem, repair your installation of Office using the following steps:
  • Windows 7 or Windows Vista
    1. Exit Outlook.
    2. Click Start, and then click Control Panel.
    3. Then, click Programs and Features.
    4. In the list of installed products, select your Microsoft Office product and then click Change.
    5. Click Repair, and then click Continue.
  • Windows XP
    1. Exit outlook.
    2. On the Start menu, point to Settings, and then click Control Panel.
    3. Double-click Add/Remove Programs.
    4. In the list of currently installed programs, select your Microsoft Office product and then click Change.
    5. Click Repair, and then click Continue.