While working to complete a project yesterday, I received this message after opening a VSTO Excel project:
I used my search engine of choice to search for “Excel Visual Studio Design-Time Adapter” and received only a few results (< 3 pages and only the first 2-3 were relevant). Uggh.
Microsoft has an article that discusses the issue but I didn’t have any of the problems they mention.
I did see two comments somewhere that mentioned re-installing Visual Studio or Office will correct the problem. Repairing my VS installation didn’t do it but repairing Office did.
So if you have the nasty “Excel Visual Studio Design-Time Adapter” (or “Word Visual Studio Design-Time Adapter”) error, just repair your Office installation.