Creating an Excel Log File using VBA - excel

Question

I'm trying to create an Excel log file using VBA. The idea is that I have columns named Tasks and By and every time a user inputs a certain task in the column cell, the cell next to it (the By column cell) would display his user name as shown in the screenshot.
I have finished the application but every time I try to test it it gives me different results and none of these results are the intended so if some one would pay a look at the code I would be glad.
Private Sub Workbook_Open()
Application.EnableEvents = False
Application.ScreenUpdating = False
Application.Calculation = xlCalculationManual
Application.CalculateBeforeSave = False
Dim serialRange As Excel.Range
Set serialRange = ActiveSheet.Range("A2:A200")
Dim taskRange As Excel.Range
Set taskRange = ActiveSheet.Range("B2:B200")
For Each cell In serialRange
Dim rownumber As Integer
rownumber = ActiveCell.Row
Dim cellValue As Integer
cellValue = cell.Value
If (ActiveSheet.Range("A1").Value = "") Then
cellValue = Null
Else
cellValue = rownumber - 1
End If
Next
For Each cell In taskRange
If (cell.Value = "") Then
cell.Value = ""
Else
ActiveCell.Offset(2).Value = Environ("username")
End If
Next
Application.ScreenUpdating = True
ActiveWorkbook.Save
Application.EnableEvents = True
Application.CalculateBeforeSave = True
Application.Calculation = xlCalculationManual
End Sub

Answer 1

couple of issues I see with the code:
The code only runs when workbook is opened. If that is by design then fine, I moved the code to Workbook_SheetCalculate to test it
Using ActiveCell and ActiveSheet can cause some real issues. For instance, when I test the code, it puts my UserName in the cell 2 cels down from whatever cell is active, not in the column next to the cell it is evaluating. This is due to the use of ActiveCell when you SHOULD be using cell and the offset should be (0,1) not (2)
For Each cell In taskRange
If (cell.Value = "") Then
cell.Value = ""
Else
cell.Offset(0, 1).Value = Environ("username")
End If
Next
You never turn calculation back to automatic (in the last section of your code, you set it to manual, which you did in the first part of your code)
Saving the workbook should occur after you re-enable all of the event handling
Application.EnableEvents = true
Application.ScreenUpdating = true
Application.Calculation =xlCalculationAutomatic
Application.CalculateBeforeSave = true
ActiveWorkbook.Save