Selection Change Code - Value less than another problem

[Corey]

Below is the code i am using to try to alert a user than there is an overlap
in 2 times.

I have also a Worksheet_Change code than allows for a 1330, 0900 value to be
entered and converted to regular 1:30PM and 9:00AM times.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Application.Intersect(Target, Range("C11,C8")) Is Nothing Then
Exit Sub
End If
If Target.Value = "" Then
Exit Sub
If Range("C11").Value < Range("C8").Value Then
MsgBox "There is an overlap in the Times Entered." & vbCrLf & "The next
Start Time needs to be equal or greater than the previous Finish Time.", ,
"Title ...."
End If
End If
End Sub
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I am trying to get the above code to show the msgbox if the time entered
into Cell C11 is a lesser time than the time in Cell C8, with out
prompting the user if the C11 Cell is left empty either.

Can someone assist ?

thanks