Normally to reset or put the toolbar back to the default configuration you would right-click on the blank area next to the buttons or menus, choose customize, click on Reset.
To reset it manually go to Start, Run, type regedit32, go to HKEY_CURRENT_USER, Software, and delete the entire DMPro7 Command Bar key (folder).
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft and Design Manager cannot guarantee that certain problems can be solved. Modify the registry at your own risk.