Modifying a table in SQL 2008 Mgt Studio

When adding a field or making other changes that requires a table be dropped and re-added, you may receive an error like 

"Saving changes is not permitted. The changes you have made require the following tables to be dropped and re-created. You have either made changes to a table that can't be re-created or enabled the option Prevent saving changes that require the table to be re-created."

If that happens, you need to update the management studio options as described here.