Error : Saving Changes in not permitted...

Management Studio Error : Saving Changes in not permitted. The changes you have made require the following tables to be dropped and re-created.

Menu >> Tools >> Options >> Designers >> Uncheck "Prevent Saving changes that require table re-creation".

Thanks to : https://blog.sqlauthority.com/2009/05/18/sql-server-fix-management-studio-error-saving-changes-in-not-permitted-the-changes-you-have-made-require-the-following-tables-to-be-dropped-and-re-created-you-have-either-made-changes-to-a-tab/