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Solution

1. Open Excel and go to File > Options > Add-ins.
   

   

   
   Here you can see the disabled Pricefx ExcelClient COM Add-in.
   

2. At the bottom of this dialog go to Manage > Disabled Items.
   

   

3. Enable Pricefx ExcelClient addon.

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Excel will show you:

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When you click the Debug button:

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In Visual Studio, you cannot see any exception, even if you enable stop on all exceptions. But you can include ExcelDna.Integration project to your solution and run it again. Then you can see the following error while invoking a COM object. Here is ExcelDna part of the solution:

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