1. Select Internet Options from the Tools menu
2. In Internet Options dialog box select the Security tab.
3. Click Custom level button at bottom. The Security settings dialog box will pop up.
4. Under Scripting category enable Active Scripting, Allow paste options via script and Scripting of Java applets
5. Click OK twice to close out.
6. Hit Refresh
Check if he has any other "protective" applications on his computer. Norton Internet Security completely removed the navigation section on a web application that we built at my last company.
Also, is he getting any errors? Check the lower left corner for a yellow triangle. If it is there, double-click it and note the error. Post back with the error if there is one.