What would cause the error handler to not work?

Hello natefarm,

When testing objects it is a good practice to assign the object to an object variable first rather than select it straight away. This method allows you check if the object was set and prevent the system from overriding your error handler. The changes are in bold text.

Sub CopyAllComments()
  Dim Sht As Object
    iResult = vbOK
Restart:
    Call SetDefaultPath
    PathName = Application.GetOpenFilename("Microsoft Office Excel Workbook(*.xls),*.xls", 2, MsgTitle)
    On Error GoTo OpenFailed
    Workbooks.Open PathName
    On Error GoTo 0

    On Error GoTo FindSheetFailed
      Set Sht = ActiveWorkbook.Sheets(ThisWorkbook.ActiveSheet.Name)
      If Not Sht Is Nothing Then Sht.Select
    On Error GoTo 0

    Exit Sub
OpenFailed:
    If PathName <> False Then
        MsgBox "Unable to open " & PathName, vbOKOnly, MsgTitle
    End If
    iResult = vbCancel
    Exit Sub
FindSheetFailed:
    MsgBox ThisWorkbook.ActiveSheet.Name & " sheet not found on " & ActiveWorkbook.Name
    ThisWorkbook.Activate
    iResult = vbCancel
End Sub

Hello natefarm,

To troubleshoot this further, I would need to see the workbook. Can you post a copy of it?

You won't need any:
And you'd better avoid activate and select in VBA.

Sub CopyAllComments()
  c00=ThisWorkbook.ActiveSheet.Name
  PathName = Application.GetOpenFilename("Microsoft Office Excel Workbook(*.xls),*.xls", 2, MsgTitle)
  if dir(pathname)="" then exit sub
 
  Workbooks.Open PathName
  if not Evaluate("isref(" & c00 & "!A1)") then exit sub
End Sub