If you’re using SQL Server Management Studio Express under Windows Vista and see either of these errors:

CREATE DATABASE permission denied in database 'master'

or

The database [Name] is not accessible. (Microsoft.SqlServer.Express.ObjectExplorer)

Here’s the fix:

  1. Close SQL Server Management Studio Express

  2. Open your start menu and locate that program.

  3. Right-click on the Management Studio and choose ‘Run as Administrator’

  4. Fixed!

I swear the simplest solutions can be the hardest to find - hopefully this saves someone (or my forgetful self!) some aggravation.