Excel Tracking Read Only Clicks

Hi All,

Hope your all ok.
I have searched everywhere and cannot find an answer so hopefully you can help. Im quite new to VBA so im struggling a bit .

I have a spreadsheet that I need to update to to present weekly information, other users then have read only access so they can check for any updates. I need to log which users are looking at the sheet, to see if it is actually being used.

I have tried VBA such as
Private Sub Workbook_Open()
With Sheets("Log")
lastrow = .Cells(Rows.Count, "A").End(xlUp).Row + 1
.Cells(lastrow, 1) = Environ("Username")
.Cells(lastrow, 1).Offset(, 1).Value = Now
End With
ActiveWorkbook.Save
End Sub

Which does the job, but i cannot set the sheet as Read Only as it just saves another copy of the sheet.
Im looking for a way of recording who is going into the sheet (Read Only), so i was thinking, is there a way of tracking which user has clicked on the Read Only option and when they clicked (date time etc), the sheet is on a shared network and i dont have any authority access.

I hope that makes sense.

Thanks
Slice