VBA out of stack space

I am looking to use worksheet_change to check a cell once it is changed and then carry out a series of processes on related cells if the cell in question is now blank. SO the idea is if the first column (B in this case) is blanked (it would usually show a date) then the value of a check box is changed (column R is where the linked cell is).

The code is as follows:

Private Sub Worksheet_Change(ByVal Target As Range)

     If Range("B" & Target.Row).Value = "" Then
     Range("R" & Target.Row).Value = False
    End If


End Sub

This works fine if the cell contains anything. But if I edit the cell, remove the date and hit return I get an out of stack space error at the If stage. Is there a problem evaluating a blank cell or something?

As always thanks in advance.