You try to deploy a SharePoint 2010 solution from Visual Studio 2010 and receive the following error:
Could not load the Web.config configuration file. Check the file for any malformed XML elements, and try again. The following error occurred: The given key was not present in the dictionary.”
While the message isn’t very specific on what key wasn’t present in which dictionary it’s at least unique so you can find posts like this :-).
And even better–it has a simple solution: make the site URL’s host you deploy your solution to match SharePoint’s default alternate access mapping.
For example in SharePoint’s Central Administration, Alternate Access Mappings you have
|Internal URL||Zone||Public URL for Zone|