hi.
try this with a copy of the file:
Sub del_dupe_rows_another_sheet()
Dim i As Long, LastRowSh1A As Long, LastRowSh2A As Long
Dim LookUpRange As Range
With Worksheets("Sheet1")
LastRowSh1A = .Cells(.Rows.Count, "A").End(xlUp).Row
Set LookUpRange = .Range("A2:A" & LastRowSh1A)
End With
With Worksheets("Sheet2")
LastRowSh2A = .Cells(.Rows.Count, "A").End(xlUp).Row
For i = LastRowSh2A To 2 Step -1
If Application.CountIf(LookUpRange, .Cells(i, "A")) > 0 Then .Rows(i).Delete
Next i
End With
End Sub
Sub clear_dupe_cells_another_sheet()
Dim i As Long, LastRowSh1A As Long, LastRowSh2A As Long
Dim LookUpRange As Range
With Worksheets("Sheet1")
LastRowSh1A = .Cells(.Rows.Count, "A").End(xlUp).Row
Set LookUpRange = .Range("A2:A" & LastRowSh1A)
End With
With Worksheets("Sheet2")
LastRowSh2A = .Cells(.Rows.Count, "A").End(xlUp).Row
For i = LastRowSh2A To 2 Step -1
If Application.CountIf(LookUpRange, .Cells(i, "A")) > 0 Then .Cells(i, "A").Clear
Next i
End With
End Sub