Check if a column is blank

[bcmk29]

The below code works fine when the selected column has more than 5 values. But, when the selected column is empty the code doesn't validate the >5 condition and throws a run time error. Can someone please help?

abc:
    n = Selection.Cells.SpecialCells(xlCellTypeConstants).Count
    If n > 5 Then
    Set InputRng = Application.Selection
    Set ReplaceRng = tblAdmin.Range("M2:N90")
    For Each rng In ReplaceRng.Columns(1).Cells
    InputRng.Replace What:=rng.Value, Replacement:=rng.Offset(0, 1).Value, LookAt:=xlWhole, _
        SearchOrder:=xlByRows, MatchCase:=False, SearchFormat:=False, _
        ReplaceFormat:=False
    Next
    ActiveCell.Next.EntireColumn.Select
GoTo abc

 

[bebo021999]

Exit Sub if n=0:

abc:
    n = Selection.Cells.SpecialCells(xlCellTypeConstants).Count
    If n= 0 then Exit Sub
    If n > 5 Then
    .......

 

[bcmk29]

Exit Sub if n=0:

abc:
    n = Selection.Cells.SpecialCells(xlCellTypeConstants).Count
    If n= 0 then Exit Sub
    If n > 5 Then
    .......

n=0 doesn't seem to work. Because if the column is empty it doesn't give any value(0).

 

[bebo021999]

Or:

if n is nothing then Exit sub

Or even

If Selection.Cells.SpecialCells(xlCellTypeConstants) is nothing then Exit Sub

?

 

[bcmk29]

Or:

if n is nothing then Exit sub

Or even

If Selection.Cells.SpecialCells(xlCellTypeConstants) is nothing then Exit Sub

?

I tried both the codes, it throws me Run Time Error 1004, No cells were found.