Trouble Shoot Why VBA Stops running mid macro and never finishes execution - vba

Question

As the title suggests, I was running the below macro. Weirdly enough the msgBox never prompts me with an End Time nor does an error message pop up when the macro stops running. The data in the folders is pretty straight forward stuff, however there are roughly a thousand files its going through
Any pointers on how to trouble shoot this myself? This is something I need to get better at, so suggestions on what to do to figure it out would be nice.
Sub AbesLoop()
Dim wbk As Workbook
Dim ws As Integer
Dim Filename As String
Dim path As String
Dim rCell As Range
Dim rRng As Range
Dim wsO As Worksheet
Dim StartTime As Double
Dim SecondsElapsed As Double
Dim sheet As Worksheet
Application.ScreenUpdating = False
Application.DisplayAlerts = False
Application.Calculation = xlCalculationManual
StartTime = Timer
'On Error Resume Next
path = "PATHtoStuff" & "\"
Filename = Dir(path & "*.xl??")
Set wsO = ThisWorkbook.Sheets("Sheet1")
Do While Len(Filename) > 0
DoEvents
Set wbk = Workbooks.Open(path & Filename, True, True)
ws = wbk.Worksheets.count
'For i = 1 To ws
For Each sheet In ActiveWorkbook.Worksheets
If sheet.Index > 1 Then
Set rRng = Range("b1:b308")
For Each rCell In rRng.Cells
If rCell <> "" And rCell.Value <> "Not Tested" And rCell.Value <> 0 Then
wsO.Cells(wsO.Rows.count, 1).End(xlUp).Offset(1, 0).Value = rCell
wsO.Cells(wsO.Rows.count, 1).End(xlUp).Offset(0, 1).Value = rCell.Offset(0, -1)
wsO.Cells(wsO.Rows.count, 1).End(xlUp).Offset(0, 2).Value = Mid(Right(ActiveWorkbook.FullName, 15), 1, 10)
End If
Next rCell
End If
Next
'Next i
wbk.Close False
Filename = Dir
Loop
Application.ScreenUpdating = True
Application.DisplayAlerts = True
Application.Calculation = xlCalculationAutomatic
SecondsElapsed = Round(Timer - StartTime, 2)
MsgBox "This code ran successfully in " & SecondsElapsed & " seconds", vbInformation
End Sub
Edit: turns out that for some reasom the loop code is looking at sheet tab 1. I changed the code to try and account for that but for some reason is is still looking at the first page. The error is a "mismatch type" before the dashboard on the first sheet (which I keep trying to circumvent) keeps running into a formula error.

Answer 1

When working in VBA that's part of an application it's important to use the objects provided by the application, rather than generalized Selection or ActiveWorkbook, etc. This code is doing that, which is good :-)
At the same time, however, VBA needs to be able to uniquely identify object with which it should work. With "Selection" or "Active[Thing]" that's not necessary, so this step isn't something easily learned using the macro recorder.
In the case of the code in this question
Set rRng = Range("b1:b308")
It's not clear to Excel from which worksheet the Range should be taken, so it's defaulting to the first worksheet in the workbook. Instead, use:
Set rRng = sheet.Range("b1:b10")"