seems to think that any file ending in .config must be an application configuration file.
This is not the case. I have Nini and spring.net files that end in .config. R# incorrectly reports errors for any file with a .config extension that does not adhere to the ".net configuration file schema".
The attached example solution contains a project with two files, neither of which are "app.config" files.
AnyOldFile.config contains well-formed XML, but R# complains that it is not valid, despite not being associated with a schema.
ThisIsMyFile.config is not even an XML file and R# complains that the file contains illegal XML.