Option Explicit

Private Sub Command1_Click()
' welches Datum ist ein Samstag in der jeweiligen Kalenderwoche ???
Dim d As Date

    If (Val(Text1.Text) < 0) Or (Val(Text1.Text) > 52) Then Exit Sub

    d = CDate("01.01.2004") + (Val(Text1.Text) - 1) * 7
    d = d + 5 - Weekday(d, vbMonday) + 1
    Label1.Caption = d
     
End Sub

Private Sub Form_Load()
    Text1.Text = "21"
End Sub