Data Conflict in LINQ

Question

When making changes using SubmitChanges(), LINQ sometimes dies with a ChangeConflictException exception with the error message Row not found

Answer 1

The error "Row not found or changed" also will appear sometimes when the columns or types in the O/R-Designer do not match the columns in the SQL database, especially if one column is NULLable in SQL but not nullable in the O/R-Designer.

So check if your table mapping in the O/R-Designer matches your SQL database!