Open read-only without getting message

Question

I have excel vba. As soon as I open excel file, the UserForm also opens without opening WorkBook. I can open Workbook with a button click but I want it to be read-only and not editable.

Now I have activated write protection under File -> Info -> write protection. Now when I open the excel file the message appears:

"The author would prefer you to open 'file.xlsm' read-only - unless you need to make changes. Open read-only?"

That's not what I want. Is there a way to ignore the message or to automatically confirm with "yes" so that when someone opens the excel file, the message does not appear?

Note: I dont want to use the code

Set wb = Workbooks.Open(Filename:=MyFile, ReadOnly:=True)

because i directly open UserForm when i open excel and workbook is not displayed, so i can't use this code. if you want to know how I open a file, here is also my code on how to open UserForm without opening workbook. Code in my ThisWorkBook:

Private Sub Workbook_Open()
    showLoginForm    
End Sub

Code for showLoginForm:

Sub showLoginForm()
    If isSheetVisible Then
        ' Only Hide this workbook and keep the other workbooks visible
        ThisWorkbook.Windows(1).Visible = False
    Else
        ' There is no other workbook visible, hide Excel
        Application.Visible = False
        ThisWorkbook.Windows(1).Visible = False
    End If
    UserForm5.show vbModeless
End Sub