Getting “Site Only contains Core Files” when Language resources are altered in a bad way.
Starting with a perfectly good working site, some languages need to be added in the Views.xml to support them. These languages are Japanese, Korean, Vietnamese, Kazakh, Malay etc. When adding those languages us programmers immediately think of the corresponding Top Level domain names for those countries as the Language id : jp, kr, vn, kk, and my. In this list only the kk turns out to be correct. They should be ja, ko,vi, kk and ms.
When this file with the wrong id’s gets deployed to an EPiServer 7.1 site the site will display “This site only contains core files” grey screen. I think it is because the initialization ends in an exception. It would be nice if this exception bubbles up and be displayed. This blog post serves as a warning to check your language id’s and not rely on your knowledge of top level domain names.