Pass The Contents Of A Listbox To A Function To Sort It Into Alphabeticalorder

I'm trying to do is pass the contents of a listbox to a function to sort it into alphabeticalorder. I get a error saying object required

Sub PopulateAll()
Dim lgLastRow As Long
Dim lgRowCounter As Long
Dim intCounter As Integer
Dim olb As MSForms.ListBox

For intCounter = 0 To UBound(vAllEnv)
Me.lstAll.AddItem (vAllEnv(intCounter))

Next intCounter

Set olb = frmOptions.lstAll.........................