Code, that disables save, save as and close commands

Each of the worksheets in my model use A1 as a control cell for any errors and inconsistencies. My aim is to disable save and close commands in case A1 is not equal to 0 in any of the worksheets.

The code I currently use for that purpose is as follows.

Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)

Dim Rng As Range
Dim ws As Worksheet

For Each ws In Worksheets
Set Rng = ws.Range("A1")

If ws.Range > 0 Then
Cancel = True
lReply = MsgBox("Please correct...", vbOKOnly)

End If
End Sub

Something however is not OK and it gives errors. Furthermore, the disabling of close command is not covered.

Please help me update it.