VBA Message box to show if user tries to enter info into a cell when another cell is empty

[RJSIGKITS]

Hi.

Could someone please help me with this, as I can't get it to work right.

I need to add a message box VBA to my worksheet which forces a user to enter other data before they can enter data into a specific cell, as follows:

User needs to add data on the worksheet, which fills Cell H1, in order to then be able to use the Data Validation dropdown selector in cell D14. If they have not entered the required data, an error message box is to show warning the user that they must add the required details before continuing.

Thanks

 

[footoo]

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Target.Address = "$D$14" And [H1] = "" Then
    MsgBox "Enter data in H1"
    [H1].Select
End If
End Sub