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Changing AssemblyVersion to older version prevents COM Add-in from loading?

Dec 9, 2012 at 4:38 PM

I've built a small Outlook COM Add-in using Netoffice.

I'm running Outlook 2010 (64-bit) on my local machine and added a post-build step that uses the appropriate version of regasm (found here

Everything was working fine.

I then decided to start versioning my assembly.  So I changed the AssemblyVersion found in the Add-in's AssemblyInfo.cs from to . I built and ran Outlook.  Everything continued to work fine.

I then put the AssemblyVersion back to, and built and ran Outlook.  The Add-in did not load.  The COM Add-Ins window reports "Not loaded.  A runtime error occurred during the loading of the COM Add-in."

I then changed the AssemblyVersion back to . Built and ran and everything worked fine.

I can live with this... but its bugging me that I can't figure out what's happening.  I've tried manually unregistering and registering the assembly (I'm using the /codebase option).  I do not see my assembly in the GAC.  I see nothing in DbgView.  

Is the Assembly version cached somewhere?  Is Netoffice caching it and checking that the version its about to load isn't older?  

Any light you can shed would be helpful.  Thanks!

Dec 10, 2012 at 3:43 PM

you have to use regasm again after changing. :-)