My code detects an "X" in one column of a range; if present, that row is
hidden, and a new range is set to the intersection of that range and the
visible cells only of that range. Underneath is the formula
=COUNT((col7 rng1Work))
which counts the number of items in the intersection of the column range and
the visible cells range.

It all works fine - until I "X" out all five rows of the original range.
Then the COUNT doesn't change from whatever it was previously. I'm assuming
that since it hides all the rows, and there are no visible cells to
intersect with, the INTERSECT function fails, and my On Error Resume Next
flows right over it without burping - and without resetting my range.

How can I detect a NULL (?? correct term??) range, or the lack of a range,
when this occurs? (Note: the original range covers 5 rows, but this can
vary.)

Ed

' Hide rows with value of "X"
For i = 1 To rngThis.Rows.Count
If rngThis.Cells(i, 1).Value = "X" Or _
rngThis.Cells(i, 1).Value = "x" Then
rngThis.Rows(i).Hidden = True
End If
Next i

' Reset range to visible cells only
Range(strName).SpecialCells(xlVisible).Select
Set rngVis = Selection
Set rngThis = Application.Intersect(Range(strName), rngVis)
Range(strName).Rows.Hidden = False
rngThis.Name = strName & "Work"

Calculate