How to prohibit changing the subject of the letter and the mailing list in MS Outlook?

Question

Visual Basic

Good afternoon everyone!
Please help me understand the following:
The subject of the letter is formed automatically in the code. Once opened, the email submission form should not allow the user to change it.

Public Sub Новое_Письмо(Theme As String, AddressList As String)   
...
    With newMail
        .Subject = Theme
        .To = AddressList
        .BodyFormat = olFormatHTML
        .htmlBody = htmlBody
        .Display
 ...
    End With

Is it possible to prevent in the VBA code from changing the subject of the letter and the mailing list in MS Outlook after opening the form?
If you open the form designer, there is a Locked property on the Subject(TextBox) field, which should be sufficient. But it is not possible to access it through the code.

Answer 1

Thanks, but there is no exchange yet. Something needs to be done in this situation.