Developers are already done steps described in the articles How to determine the name of the instance of the Database Engine and How to verify that Database Engine is running. Now they should follow the next steps:
1. On the File menu, click Connect Object Explorer.
The Connect to Server dialog box opens. The Server type box displays the type that was last used.
2. Select Database Engine.
3. In the Server name box, type the name of the instance of the Database Engine.
4. Click Connect.