O/R Designer Validation failed - during clean?

Question

------ Clean started: Project: DataService, Configuration: Debug Any CPU ------
O/R Designer validation failed for file: a.dbml
O/R Designer validation failed for file: b.dbml
O/R Designer validation failed for file: c.dbml
O/R Designer validation failed for file: d.dbml
O/R Designer validation failed for file: e.dbml
O/R Designer validation failed for file: f.dbml
Error: The operation could not be completed. Unspecified error 

This error is intermittent. Sometimes the clean is fine, sometimes this happens.

I'm running VS2008 version 9.0.30729.1 SP - 64bit.

Is there some way I can disable the O/R designer's validation or otherwise stop this from occuring?

Answer 1

I had to close Visual Studio and reopen it. Solved this for me. In another case I had to roll back my DBML file, then close Visual Studio, and reopen it.

Looks like a bug for Microsoft to fix.

Answer 2

This problem appeared after I copied a property in a table. For some reason the copied property had the same storage name. Deleting this storage attribute in dbml xml for those copied properties solved the issue.

So the source of this problem is most likely some error in the dbml file. If you have version control, check what you changed and maybe you'll spot the error.