Call Application.OnTime with fully qualified path to sub? - vba

Question

I have a spreadsheet that I implemented a timer in to automatically update a formula every 10 seconds. Everything was working great until I would open another spreadsheet. My assumption was that it was still trying to run Timer() on the wrong sheet. So, I tried switching to absolute calls. Here is my full code:
Dim TimerActive As Boolean
Sub StartTimer()
Start_Timer
End Sub
Private Sub Start_Timer()
TimerActive = True
Application.OnTime Now() + TimeValue("00:00:10"), "timetrack.xlsm!Tracker.Timer"
End Sub
Sub Stop_Timer()
TimerActive = False
End Sub
Sub Timer()
Dim tracker As Worksheet
Set tracker = Workbooks("timetrack.xlsm").Sheets("Tracker")
tracker.Range("O1").Value = "Timer Stopped"
'On Error Resume Next
If TimerActive Then
tracker.Range("O2").Value = Time
Application.OnTime Now() + TimeValue("00:00:10"), "timetrack.xlsm!Tracker.Timer"
tracker.Range("N:N").Calculate
End If
tracker.Range("O1").Value = ""
End Sub
Specifically, I'm getting an error on the Application.OnTime line:
Cannot run the macro ''S:\OneDrive...!docs\timetrack.xlsm'!Tracker.Timer'. The macro may not be available in this workbook or all macros may be disabled.
The path that shows up in the error is correct. What is wrong? What's weird is it seems to run it in the StartTimer() sub without issue.

Answer 1

To refer to a procedure in a worksheet, you need to use the WorkSheet.CodeName and not the WorkSheet.Name :
Application.OnTime Now() + TimeValue("00:00:10"), ThisWorkbook.Name & "!" & Me.CodeName & ".Timer"

Answer 2

You'll need to activate the desired workbook prior to making changes to the cells within.
Before accessing the contents within the workbook, try adding:
Workbooks("timetrack.xlsm").Activate
If the macro that runs is in "timetrack.xlsm" you could also use the following code to avoid referencing the workbook name:
ThisWorkbook.Activate
ThisWorkbook refers to the workbook in which the macro resides.