The following error was encountered while changing the collation: <Error>. (Visual Database Tools)
The collation was not changed because of the underlying problem described in the message. Changing a column's collation is akin to changing its data type. That is, after you change the collation, the Visual Database Tools validate the column's data type. This validation can uncover a number of problems, including:
The modification enlarges the column, which in turn enlarges an index beyond the maximum size for indexes.
The modification is incompatible with existing data values in the column.
Choose a different collation for the column or fix the underlying problem.