I am a newbie, therefore my code will be like this... conservative but working. (For learning purposes only, please follow the code of the Excel MVPs).
Sub ActiveRC()
If ActiveCell.Column() <> 1 Or ActiveCell.Row() < 6 Or ActiveCell.Row() > 1000 Then
MsgBox "WRONG CELL SELECTED.", vbOKOnly + vbInformation, "Hello!!!"
Else
MsgBox "YOU ARE INSIDE THE RANGE.", vbOKOnly + vbInformation, "Yahoo!!!"
End If
End Sub