Saving changes is not permitted

When you use SQL Server 2008 and try to add a new column in the existing table, you get the following alert and cannot proceed with the modification on the table schema.

This happens when you install a brand-new SQL Server 2008 on your machine. The solution to the above is to disable "Prevent saving changes that require table re-creation" thru Tools-> Options-> Designers-> Table and Database Designers.