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I created an Excel VSTO Add-in using the provided template in Visual Studio. The add-in is working great. However, when the add-in is loaded in Excel other applications that export to Excel fail when attempting to initialize Excel. It's like the Add-in may be breaking the COM connection the exporting application is making with Excel. 
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There are multiple reasons why you may get that error. I'd suggest reviewing all posts at https://stackoverflow.com/questions/22062284/server-execution-failed-exception-from-hresult-0x80080005-co-e-server-exec-fa.
Also you may find the Error when you start many COM+ applications: Error code 80080005 -- server execution failed article helpful.
Before, I was installing the add-in using a batch utility, by placing the files were they need to be and setting the necessary registries in:
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Excel\Security\Trusted Locations\
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\Excel\Addins
If I use a ClickOnce installer instead, everything works as it should. What else is the ClickOnce installer doing?
Why do you think your add-in is causing the issue? The error message doesn't mention that. The problem can be in Excel only or technology you are using for automating Excel. Is it a service?
The issue only occurs when the add in is loaded.
Here's a video that might clarify what's happening.
https://wisdot.box.com/s/zkvjo00zfqja4itbz0vx5mti6r3l52ya
I think I found what is causing it. In the registry:
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\Excel\Addins\
for the add in "Manifest" value, if I have "|vstolocal" at the end of the path, I get the error. If I remove "|vstolocal", everything works great. I thought we were supposed to have "|vstolocal" appended to the end of the path???
Is it on your development machine?
See Deploy an Office solution by using Windows Installer for more information what steps should be done to register the add-in.