Why do the add-ins I am workign on no loger appear in Pro?

Question

I'm working on some ArcGIS Pro add-ins and all of the sudden it appears that I cannot see or access the add-ins in Pro.  I'm running the add-ins from Visual Studio 2015 debug mode, as documented in the ArcGIS Pro SDK Community Samples.  However, the add-ins are no longer visible anywhere in Pro, either in the Add-in tab or elsewhere.  I didn't change any settings in Pro or make any other system changes that I'm aware of that could possibly affect ArcGIS Pro.  I do not see anything in the Add-In manger when Pro starts in debug mode:

How do I set Pro to once again detect the add-ins I am working on in Visual Studio?

System specs: Windows 7 64-bit, ArcGIS Pro 2.0.0, Visual Studio 2015

mfcallahan · Answer

Thank you for the reply - I did a reboot immediately after posting the question and it seems to have solved the issue.  I am now seeing the add-in tab, custom tabs, and all the controls when debugging. The project is also listed the add-in manager.  To answer the question from your reply, the add-ins were created for version 2.0, but I do appreciate the links you provided.  The migration guide was very helpful.

Wolf · Answer

I would first check the desktopversion attribute of the AddInInfo tag in the config.daml file.   If you created the add-in with a pre 2.0 version of the SDK the add-in is not run-time compatible with ArcGIS Pro 2.0.  If you migrate a 1.x add-in to 2.0 you have to change the desktopversion attribute to 2.0.0 as well (when you recompile your add-in) for your add-in to work under 2.0.    We provided an FAQ with some links for more detailed information on how to diagnose this issue: https://github.com/Esri/arcgis-pro-sdk/wiki/FAQ#why-does-arcgis-pro-not-load-my-add-in .  There is also a ProConcept document on migrating to 2.0:  https://github.com/Esri/arcgis-pro-sdk/wiki/ProConcepts-2.0-Migration-Guide