Change combobox list based on option button

I have two buttons:

Private Sub Optionbutton1_Change()
Call UserForm_Initialize
End Sub

Private Sub Optionbutton2_Change()
Call UserForm_Initialize
End Sub

And code below:

Private Sub UserForm_Initialize()
Dim cPart As Range
Dim ws1 As Worksheet
Dim ws2 As Worksheet
Set ws1 = Worksheets("Sheet1")
Set ws2 = Worksheets("Sheet2")
Dim optbut As Integer

If Optionbutton2 Then 

        For Each cPart In ws1.Range("List1")
      With Me.CmbSiteName
        .AddItem cPart.Value
        .List(.ListCount - 1, 1) = cPart.Offset(0, 1).Value
      End With
    Next cPart


ElseIf Optionbutton1 Then

    For Each cPart In ws2.Range("List2")
      With Me.CmbSiteName
        .AddItem cPart.Value
        .List(.ListCount - 1, 1) = cPart.Offset(0, 1).Value
      End With
    Next cPart
    
End If

Me.CmbSiteName.SetFocus
End Sub

By default:
Optionbutton1=False
Optionbutton2=True

and 3 steps:

When I run User form - it's OK (looking at List 1)
When I click Optionbutton1 - it's OK (looking at list 2)
When I now click back to Optionbutton2 it remains at List 2.. Why doesn't switch to List1?

could you attach workbook with dummy data ?

I modified your code into this, I hope it is what you need

Private Sub UserForm_Initialize()
Dim cPart As Range
Dim ws1 As Worksheet
Dim ws2 As Worksheet
Set ws1 = Worksheets("Sheet1")
Set ws2 = Worksheets("Sheet2")
Dim optbut As Integer

cmbSiteName.Clear 'clear combobox before update

If OptionButton2 Then

    'old
    'For Each cPart In ws1.Range("List1")
    '  With Me.cmbSiteName
    '    .AddItem cPart.Value
    '    .List(.ListCount - 1, 1) = cPart.Offset(0, 1).Value
    '  End With
    'Next cPart

    'new
    With cmbSiteName
        .ColumnCount = 2
        .List = ws1.Range("list1").Value
    End With

ElseIf OptionButton1 Then

    'old
    'For Each cPart In ws2.Range("List2")
    '  With Me.cmbSiteName
    '    .AddItem cPart.Value
    '    .List(.ListCount - 1, 1) = cPart.Offset(0, 1).Value
    '  End With
    'Next cPart
    
    'new
    With cmbSiteName
        .ColumnCount = 2
        .List = ws2.Range("list2").Value
    End With
End If

Thx maczaQ!

CmbSiteName.Clear did the trick...
I left rest of previous code because it create 2 columns in combobox.

I can upload file when I finnish it

my code creates two columns too (without for each loop)

hmm.. didn't work for me at the first time... I'll take a look again... Probably I need to redefine lists.

of course your list1 and list2 should be range for 2 columns

Yea, I thought so... I'll have a look and then return you info...

Much easier with your approach. Everything working.. Thx.

Final file, as I promised... Too large for upload so I have to put it on external site: http://www.2shared.com/file/N1SpWd77/kmlkmzfiles.html

Everything working now (as I test it but need few more days)... But you'll see codes aren't example of eleganxy (mostly by recording). So any suggestions are wellcome, but not obligatory

And of course, free for further sharing.