Type Mismatch error.

[His Nibbs]

Please post your code within [CODE ] [/CODE ] tags without the spaces.

Try:

If Radio(0).Checked Then
  Msgbox "XP"
'objTSEnvironment("InstallOS") = "2"
ElseIf Radio(1).Checked Then
'objTSEnvironment("InstallOS") = "1"
  Msgbox "W7"
End If