I have been running into this odd error off and on for the past week with the code generated by the Linq to SQL designer. I kept on getting Error 1 Build failed due to validation errors in C:\xxx\DB.dbml…. when I tried to build. Thanks to google (a developers best friend) I ran into a blog entry by Rick Strahl that talked about resetting Visual Studio Packages. Well it turns out this is solves my issue but I had to follow these steps to get it to work.
- run devenv /ResetSkipPkgs
- clean the solution
- recompile
I really hope they fix this with SP2 or in VS 10.