Cannot execute as the database principal because the principal "dbo" does not exist I restored a backup of a database from SQL Server 2008 R2 to SQL Server 2012.

When I try to access a particular page of my application, I get this error:


  Cannot execute as the database principal because the principal "dbo" does not exist


It works with my 2008 R2 project perfectly. How can I resolve this issue?
You need to give the database a valid owner. Use the ALTER AUTHORIZATION command to do this:

ALTER AUTHORIZATION 
ON DATABASE::[DatabaseName]
TO [A Suitable Login];


Related Knowledge Base article

Note the sp_changedbowner system stored procedure has been deprecated in favour of ALTER AUTHORIZATION.