you need a Checkbox for that purpose because if you have only one option button then you cannot disable the combo again. try this:
VB Code:
Private Sub Form_Load()
Combo1.Enabled = False
End Sub
Private Sub Check1_Click()
If Check1.Value Then
Combo1.Enabled = True
Else
Combo1.Enabled = False
End If
End Sub
if you still want to use an option button, and you only have Option button and the combobox on your form, then put the option button within another container like PictureBox or Frame and in the above mentioned code, replace Check with Option.
Harsh Gupta.