RmDir function doesn't work in LOOP! [simple help]

[soothsayer]

why doesn't this work?

Private Sub Command1_Click()
Dim a
Dim b
b = InputBox("Enter your name")
For i = 1 To 50
 a = "c:/windows/desktop/" & b & i
 MkDir a
Next i
End Sub

Private Sub Command2_Click()
Dim a, b
b = InputBox("Enter ur name")
For i = 1 To 50
    a = "c:/windows/desktop/" & b & 1 & "/"
    RmDir a
Next i
End Sub