[RESOLVED] Combobox

Suppose you have a userform. Once you added n items to a combobox, the user is supposed to select one of the n items.
Then you save the value as:
combovalue = cboRightValues.Value
But the user can write something in the combobox case by mistake or laziness.
How can you write something like:
If combovalue doesn't belong to the n items collection of cboRightValues Then
MsgBox "Try again"
Exit Sub
End if

You do know you can change the Style property to "Dropdown List", which means that the user can only select from the list...