Combobox invalid entry question

[sharky12345]

I've set a Combobox on a userform to only allow matches but at the moment users can still type in their own free text, which generates a standard Microsoft error message.

What I'd like is for a custom message to appear, something like 'You must select from the drop down list', which on clicking Ok would clear the Combobox - anyone?

 

[Worf]

How is the combo box populated? From range, array? See if this example is useful:

' UserForm module
Dim a, b

Private Sub UserForm_Initialize()
a = Array("50", "75", "100")
With Me.ComboBox1
    .List = a               ' populate
    .MatchEntry = fmMatchEntryComplete
    .MatchRequired = True
    .EnterFieldBehavior = fmEnterFieldBehaviorSelectAll
End With
End Sub

Private Sub ComboBox1_Change()
b = Filter(a, Me.ComboBox1.Value, True, vbTextCompare)
If UBound(b) = -1 Then
    MsgBox "You must select from the dropdown list"
    Me.ComboBox1.Value = ""
End If
End Sub