The language for this file does not support the necessary code parsing and generation services
Complete error message: Please ensure the file you are opening is a member of a project and then try to open the file again.
This error most likely resulted from right-clicking a file in Solution Explorer or the Open File dialog box and choosing Open With... on a file that is in a project that does not support designers.
To correct this error
- Ensure the file you are opening is a member of a project, and then try to open the file again.