customizing web browser control visual studio C#

hi i m using webbrowser control to show the visio files using C# winforms.. when i right click on the webbrowser tool bar it allows me to customize the tool bar by adding a link (open the file in microsoft visio).. i want to disable that thing user is allowed only to view the visio file in the webbrowser control of toolbaox... user is not allowed to open that file in microsoft visio ... for security concerns.. can i control right click on tool box or some other smart way to do that..

regards