Highlight Entire Rows In VBA Based On Entry In Column A

I am trying to write a procedure to highlight entire rows in VBA based on a entry in column A.

I have the below which works for say 1000 rows but breaksdown when I have 58,000 rows which is the usual amount of data I will have.

Below is the code I have so far. It appears when I debug it breaks on the red line with type mismatch.

Option Explicit
Sub RemoveBH()
Application.ScreenUpdating = False
Dim intcount As Long
For intcount = Cells(1, 1).CurrentRegion.Rows.Count To 1 Step -1

[code].....