Requirement:
How to make a workbook work only on specific days and time.
That is workbook works normally from Monday to Friday as from 8.00 am to 5 pm, otherwise if not in the specified range then read only or close workbook.
Solution:
Place the following code on ThisWorkbook Module.
Private Sub Workbook_Open()
If Weekday(Date, vbMonday) = 6 And Weekday(Date, vbMonday) = 7 Then
    MsgBox "The workbook is only allowed in weekdays.", vbExclamation
    ThisWorkbook.Close False
Else
    If TimeValue(Now) < TimeValue("08:00:00") Or TimeValue(Now) > TimeValue("17:00:00") Then
        MsgBox "The workbook is only allowed between 9 AM to 5 PM.", vbExclamation
        ThisWorkbook.Close False
    End If
End If
End Sub
Obtained from the OzGrid Help Forum.
Solution provided by sktneer.
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