Mismatch error

The code below is supposed to search an array B in column A
and highlight all the matches. I keep getting a mismatch error. Can someone help me? Thanks

Sub FindAndHighlight()

Dim FirstAddx As String
Dim LastRow As Long
Dim N As Long
Dim R As Long
Dim SrchRng As Range
Dim SrchRslt As Range
Dim SrchValue As Variant

N = Cells(Rows.Count, "B").End(xlUp)
For R = 1 To N
SrchValue = Cells(R, "B")
LastRow = Cells(Rows.Count, "A").End(xlUp).Row

Set SrchRng = Range("A1", Cells(LastRow, "A"))
Set SrchRslt = SrchRng.Find(What:=SrchValue, _
LookIn:=xlValues, _
LookAt:=xlPart, _
SearchORder:=xlRows, _
SearchDirection:=xlNext, _
MatchCase:=False)
If Not SrchRslt Is Nothing Then
FirstAddx = SrchRslt.Address
Do
SrchRslt.Interior.ColorIndex = 6
Set SrchRslt = SrchRng.FindNext(SrchRslt)
Loop While SrchRslt.Address <> FirstAddx And Not SrchRslt Is Nothing
End If
Next R

That did the trick. THANKS SO MUCH