When attempting to open a Workbook using msoFileDialogFilePicker I get a Microsoft Excel Message:- “Book is already open. Reopening will cause changes you made to be discarded – Do you want to continue” Yes/No
If choose “Yes” – that’s fine.
But if I selected the “No” option it would through a ‘Runtime Error 1004 – Method Open of Object “Workbook” failed’ message at the line highlighted due to the Workbook I am attempting to open being already open but UNSAVED.
I have inserted a Error Handler to deal with the issue of selecting the “No” option.

But of course I am still getting the Microsoft Excel Message:- “Book is already open. Reopening will cause changes you made to be discarded – Do you want to continue” Yes/No; is there any way I can suppress this message or deal with the Runtime Error 1004 in a different way.

Dim ButtonChosen As Integer
Dim ws As Worksheet
Dim fd As FileDialog, fn As String, fp As String

                'Starting this procedure from UserForm1 on Sheet in 
                                         ‘      "Time Book.xlsm"
   Application.ScreenUpdating = False 
                    'Change initial directory path "fp" to your desired folder'
            fp = "C:\Users\Me\Documents\My Documents\"
                    'Looks for files ending only in "*Invoice Book.xlsm"'
        Set fd = Application.FileDialog(msoFileDialogFilePicker)
        With fd
            .InitialFileName = fp & "*Invoice Book.xlsm"
            .AllowMultiSelect = False
                    'Lists only "*Invoice Book,xlsm" files.(Slight flaw with _
                                  'this is it also displays ALL  "File Folders" as well)
            .Show
   If .SelectedItems.Count = 0 Then
               ThisWorkbook.Activate
                    Unload Me
          Else
                fn = .SelectedItems(1)
     On Error GoTo ErrHandler1:
     Set wbInvoice = Workbooks.Open(fn)          
                      'label on UserForm displaying name of "InvoiceBook.xlsm" just opened
                Label1.Caption = Dir(wbInvoice.FullName)
                      'List on UserForm of all Sheets IN the "*Invoice Book" just opened
              For Each ws In wbInvoice.Worksheets
                    ListBox1.AddItem ws.Name
            Next ws
          End If
        Application.ScreenUpdating = True     
   End With
Exit Sub
ErrHandler1:
MsgBox "File is open but UNSAVED, Exit and go save it!"
                Unload Me
End Sub