Excel 2016 crashed when vba use saveas method on new application

Question

I try to use Workbook.SaveAs method to save a new workbook with a specific name. I found it runs fine within the Application which the code run on. But caused excel crash with a new application. What's the problem? Excel 2016 on Windows 10 Pro. Codes below:

Sub test()
    Dim this_app As Application
    Set this_app = Application
    Dim new_app As Application
    Set new_app = New Application
    new_app.Visible = True
    Dim wb As Workbook
    Set wb = this_app.Workbooks.Add
    wb.SaveAs Filename:="new_file_name1"
'above SaveAs succeed
    Set wb = new_app.Workbooks.Add
    wb.SaveAs Filename:="new_file_name2"
'above SaveAs cause excel crash
End Sub

If I use SaveCopyAs method (code below), both is fine. But I still want to know why SaveAs caused Excel crashed.

Sub test()
    Dim this_app As Application
    Set this_app = Application
    Dim new_app As Application
    Set new_app = New Application
    new_app.Visible = True
    Dim wb As Workbook
    Set wb = this_app.Workbooks.Add
    wb.SaveCopyAs Filename:="new_file_name1.xlsx"
'above SaveCopyAs succeed
    Set wb = new_app.Workbooks.Add
    wb.SaveCopyAs Filename:="new_file_name2.xlsx"
'above SaveCopyAs also succeed
End Sub

Answer 1

The following works for me (Excel 2013):

Option Explicit

Sub TestMe()

    Dim this_app    As Application
    Set this_app = Application
    Dim new_app     As Application
    Set new_app = New Application

    new_app.Visible = True

    Dim wb As Workbook

    Set wb = this_app.Workbooks.Add
    wb.SaveAs Filename:="new_file_name11"

'above SaveAs sucessed
    Set wb = new_app.Workbooks.Add
    wb.SaveAs Filename:="new_file_name22"
'above SaveAs cause excel crash

End Sub

I suppose that your problem was in app.Visible or that you already had a file named new_file_name2 , thus it crashed. Try changing the files and always add Option Explicit on the top of your code.