Sometimes right click won’t work in Excel 2010, but there is a fix for this. If right click isn’t working in Excel 2010:
- Close Excel 2010
- Navigate to C:\Documents and Settings\%username%\Application Data\Microsoft\Excel or C:\Users\%username%\AppData\Roaming\Microsoft\Excel if you are using roaming profiles
- Delete (or rename) Excel14.xlb
- Start Excel and see if this fixes the problem
If right click is still not working, you could try disabling your Excel add-ons until right click starts working again.