Backup scheduled with timer, Threads and Delegates VB.NET

I have a system on vb.net which has the function HacerBackup() that is activated with a button and saves a backup of the database on a removable device.

Then the client asked me to make automatically certain days every certain time and then the problem arose with these thread issues.

The following code is found in the event Form.Load , after some IF (If the scheduled backup is activated, what days it will do and how often)

Dim tiempo As Integer = (CInt(TablaConfiguracion.Rows(10)(1)) * 60000) 'Intervalo en minutos
Timer_Backup.Interval = tiempo
Timer_Backup.Enabled = True

Then in the Timer_Backup_Tick I call the function HagaBackup ()

Private Sub Timer_Backup_Tick(sender As Object, e As EventArgs) Handles Timer_Backup.Tick
    HacerBackup()
End Sub

But the problem is that when you perform the backup (which takes time) the program stops until it ends. I need to create another background thread to do the data compression and copy while the user is still working.

As I have no idea about Multi-Threading and what I found was unintelligible, I consulted them about methods or how they can be done.

EDITED:

I solved it using "AddHandler Timer_Backup.Elapsed, AddressOf Timer_Tick" as seen below:

    '-----------------------------------------------------------------------------------'
    'Si esta activado el BACKUP PROGRAMADO llama a la funcion HacerBackup cada X minutos'
    '-----------------------------------------------------------------------------------'
    If TablaConfiguracion.Rows(9)(1) = True Then

        Dim dias As String() = TablaConfiguracion.Rows(11)(1).Split(",")
        Dim hoy As String = Today.DayOfWeek

        'Si esta tildado el dia en preferencias'
        If dias(hoy - 1) = "1" Then
            Dim tiempo As Integer = (CInt(TablaConfiguracion.Rows(10)(1)) * 60000) 'Intervalo en minutos'
            'Aquí creo el timer y le agrego como Handler.Elapsed la dirección de memoria del subproceso Timer_Tick'
            Timer_Backup = New System.Timers.Timer()
            AddHandler Timer_Backup.Elapsed, AddressOf Timer_Tick
            Timer_Backup.Interval = tiempo
            Timer_Backup.Enabled = True
        End If
    End If

But I have a new question, I have a label in the Form_Principal which I want to show the date and time of the last backup

    Shared Sub Timer_Tick(source As Object, e As System.Timers.ElapsedEventArgs)
    If HacerBackup() = True Then
        Dim ultimo_backup As String = e.SignalTime.ToString("dd/MM/yyyy - HH:mm")
        Form_Principal.Label_Principal_UltimoBK.Text = ultimo_backup
    End If
End Sub

But when executing the instruction the label is not changed. And if I put it as private it returns the following:

  

Invalid operation through subprocesses: Control was accessed   'Label_Principal_UltimoBK' from a subprocess other than that in which   He created it.

LAST EDIT: (And Definitive Solution)

I solved it using delegates, as I show below:

Delegated function:

Delegate Sub DelegadoCambiarLabel(ByVal texto As String)

Function that changes the label:

Private Sub CambiarLabelBackup(ByVal texto As String)
    Me.Label_Principal_UltimoBK.Text = texto
End Sub

Adding to the Call function in each Tick of the timer:

    Private Sub Timer_Tick(source As Object, e As System.Timers.ElapsedEventArgs)
    If HacerBackup() = True Then
        Dim ultimo_backup As String = e.SignalTime.ToString("dd/MM/yyyy - HH:mm")
        'Creamos una instancia del delegado, llamando a la función CambiarLabelBackup'
        Dim Delegado As New DelegadoCambiarLabel(AddressOf CambiarLabelBackup)
        'Invocamos esa instancia y le pasamos como objeto el string en cuestión'
        Me.Invoke(Delegado, New Object() {ultimo_backup})
        TablaConfiguracion(12)(1) = ultimo_backup
        EscribeINI()
    End If
End Sub

And voila! All done. Thanks.