Can't add back VSTO add-in after removing it RRS feed

  • Question

  • I create VSTO outlook add-in and create installer using WIX. It works okay. But if I remove add-in using File->Options->Add-ins->Manage Com Add-ins->Remove and then try to add it back using File->Options->Add-ins->Manage Com Add-ins->Add it shows error - "xxxxx/MyAddIn.dll is not valid Office Add-in". What can be the problem? Does it same for all VSTO add-ins?
    Tuesday, November 15, 2016 5:23 PM

All replies

  • Hello Ivan,

    It is for unmanaged add-ins that implement the IDTExtensibility2 interface. In case of VSTO based add-in a loader file should be shown there typically. You need to build the add-in project in Visual Studio if you want to get it back in Office applications. 

    profile for Eugene Astafiev at Stack Overflow, Q&A for professional and enthusiast programmers

    Tuesday, November 15, 2016 9:01 PM
  • Hi,

    Do the add-in work when it is installed at the first time?

    To check if it is an environment issue, I suggest you install the add-in in other computers.

    To check if the deployment causes the issue, I suggest you deploy by using ClickOnce.



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    Wednesday, November 16, 2016 6:27 AM