Below is a short example illustrating the way I showed you and the correct way to do it.
For p = 0 To s.Length - 1
Select Case s.Substring(p, 1).ToLower()
'correct way to test for multiple cases with same outcome
'use comma between things you want to do the same action with
Case "a", "b", "c" : counter = counter + 1
'wrong way to test for multiple cases with same outcome
'this will not work
Case "a" : Case "b" : Case "c" : counter = counter + 1
End Select
Next
Select Case s.Substring(p, 1).ToLower()
'correct way to test for multiple cases with same outcome
'use comma between things you want to do the same action with
Case "a", "b", "c" : counter = counter + 1
'wrong way to test for multiple cases with same outcome
'this will not work
Case "a" : Case "b" : Case "c" : counter = counter + 1
End Select
Next