Word 2010 Add-in deployed using .msi is not loaded (VSTO 2010) RRS feed

  • Question

  • Hi all,

    I've ported an word2007 / .net 3.5 word add-in to word2010 / .net 4.0. Porting means I've created a brand new solution with brand new projects and just copied the .cs - files.

    The add-in works fine when starting inside Visual Studio 2010. Or by publishing it via Visual Studio.

    Because it should bei installed for all users, I've created a setup project (.msi) as described in MSDN. All fine. I've even signed the .dll's and added them to GAC using the installer. The Add-in is installed wihtout any error. But Word does not load at all the add-in when installed by the .msi.

    I've already searched and read all forums, blogs, etc. Nothing. I get no output from VSTO - loader at all. AddinSpy just tells me all the time "Object reference not set to an instance of an object.
       at AddInSpy.AddInData.GetData(RegistryKey addInKey, Boolean scanManagedInterfaces, Boolean scanNativeInterfaces, Boolean scanRemote, Boolean& isUncPath, Boolean& isHttpPath, Boolean& isDllPathValid, Boolean& isValidRegistration)
       at AddInSpy.Controller.EnumerateRegisteredAddIns(RegistryKey regHive, String hostName)"

    As mentioned before, the add-in can be loaded and is working when using any other method than the installer. A nice side-effect: When I rebuild the solution, the add-in is registered automatically by VS2010 under HKCU. When I select in the installer to install it "just for me", the registry entries are overwritten and the add-in is loaded. Even Addin Spy does not moan anymore.

    Could anybody give me a hint? I'm trying to solve the problem for two days now and I'm totally frustrated.

    Environment is Windows 7 (x64) / Office 2010 (x32)


    Friday, February 10, 2012 8:23 PM


  • Hi Tom,

    Thanks for posting in the MSDN Forum.

    I think your need make your issue more clearly for further research.

    In my opinion you need show your registry entry of your add-in which your installed via msi. Office 2010 32-bit have a quite different registry entry under x64 platform Window than under x86 window. I'm wondering whether your have incorrect key and value in the registry entry.

    Have a good day,


    Tom Xu [MSFT]
    MSDN Community Support | Feedback to us

    Monday, February 13, 2012 5:14 AM