Finding the amount of time being used in working with a document

[EinarOSies]

I have been working on a code to calculate the amount of time being used when closing a workbook. These are my line of code:

Sub VBA_Calculate_Minutes_Between_Two_Times()
Dim sTime As Date, eTime As Date
Dim iValue As Integer
Worksheets("OVERALL TOTAL DETAILS").Range("A41").Value2 = sTime
Now() = eTime
iValue = DateDiff("n", sTime, eTime)

MsgBox "The amount of time you used to work is " & iValue, vbInformation, ""
End Sub

The idea of my code is that when I open my workbook it should store the opening time in sheet @OVERALL TOTAL DETAILS cell A41, thus Worksheets("OVERALL TOTAL DETAILS").Range("A41").Value2 = =Format(Now,"dd/mmmm/yyyy hh:mm:ss:ms") is in the Open Event.
So when closing the workbook it should display a message box showing the used time in working with the workbook.

 

[Logit]

Paste the following in the ThisWorkbook module :

Option Explicit

Private Sub Workbook_BeforeClose(Cancel As Boolean)
    VBA_Calculate_Minutes_Between_Two_Times
End Sub

 

[EinarOSies]

Please when I run the code it gives me a run-time error '424' saying "Object required" any help