Getting error "Object library invalid or contains references to object definitions that could not be found" in an Excel-addin after installing MS Project 2010


  • I have an addin in Excel which I have run on different versions of Windows and Office without any problems.

    I am running Windows 7 and using Office 2007. My Addin worked fine until I installed MS Project 2010. After that I get the above message. I have a number of references in my Addin which probably is the cause of the problem.

    My references in the Addin are:

    Visual Basic For Applications
    OLE Automation                              
    Microsoft Office 12.0 Object Library  
    Microsoft Forms 2.0 Object Library
    Microsoft Word 12.0 Object Library
    Microsoft Windows Common Controls 6.0 (SP6)
    Ref Edit Control
    VB 6 - IObjectSafety Interface         (Used to encapsulate CtlRichTextBox)
    Microsoft XML, v6.0
    Microsoft Visual Basic for Applications Extensibility 5.3
    Microsoft Scripting Runtime

    The problem is that Excel does not give you any clues which one it could be. You only get Compile error and the error message "Object library invalid or contains references to object definitions that could not be found".

    As this is an Addin which is widely used within our company I am anxious to fix the problem. Can anybody give me hints of what I can do to find the root cause of the problem?

    BEzt regards

    Thursday, June 17, 2010 5:06 PM


All replies

  • Hello Bertil,

    After sometime of search on internet, I could not find any useful information of the error message, therefore, I think this could not be a common issue of Office 2007&2010 combination. Would you please try to give us a stable way to reproduce the issue? Also please show us the code snippet of which the issue occurs. Is this could be related with any third-party control which you referenced?


    Tim Li

    MSDN Subscriber Support in Forum

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    Please remember to mark the replies as answers if they help and unmark them if they provide no help.
    Friday, June 18, 2010 6:31 AM
  • Hi Tim,

    I continued to search the net and found my solution on this link,

    The problem is security issues regarding VBA extended runtime. You have to install an update (see link) and then remove all .exd files. I did this and now my Addin is working again. Many thanks to Lessan Vaezi who wrote the article.


    Friday, June 18, 2010 7:20 AM