When attempting to add back existing projects to a Visual Studio 2015 solution, VS gives the following error message. I have verified I have not already added a reference to the project I am trying to add. Is there a settings or cache file I need to delete or cleanup somewhere?
An equivalent project (a project with the same global properties and tools version) is already present in the project collection, with the path "D:\My\Path\MyProject.csproj". To load an equivalent into this project collection, unload this project first.
Still not sure what causes this to happen but it seems adding the dependent projects in reverse order allowed me to add all of my projects back in. So add all child projects first and then add the parent projects they depend on. The order they were added back into the solution may have caused the flakiness.