I think you will find this does the trick
RESOLUTION
WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
1.Quit all instances of Visio.
2.Click Start, click Run, type regedit, and then click OK.
3.Click the following registry subkey in the left pane of Registry Editor as appropriate:
•Visio 2003
HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Visio\Toolbars
•Visio 2002
HKEY_CURRENT_USER\Software\Microsoft\Visio\Toolbars
•Visio 2000
HKEY_Current_User\Software\Visio\Visio 2000\Toolbars
4.On the Edit menu, click Delete. The Toolbars subkey will be deleted.
5.If you are prompted to confirm the deletion, click Yes.
6.On the Registry menu, click Exit.
Registry Editor automatically saves your changes.