V Lookup Loop taking ages to run

Hi,

I've been trying to run a code which has data for approx. 35,000 rows and there is a v-lookup loop which is giving the correct results. But the challenge is, this specific module takes more than an hour (1.5 hrs) to run. Is there a way to make the code more efficient?

What I need: Col. N gets updated in CMDB_Raw Data sheet.

How: Col. A of Raw Data sheet looked up in sheet- "Master List Asset Categorization" and a matching value from Col. B is populated in Col. N of raw data sheet

Attaching the file. Also, here is my code:

[CODE]Sub Categorization()

Dim lastRow As Long, k As Long, wbk As Workbook, main_wbk As Workbook, lastrow1 As Long, range As range
Dim main_sht As Worksheet, Sheet1 As Worksheet, sht1 As Worksheet, sepr As String

Set main_wbk = Workbooks("CMDB_Production_File.xlsb")
Set main_sht = main_wbk.Sheets("CMDB - Raw Data")

main_wbk.Activate

lastRow = main_wbk.Sheets("Master List Asset Categorzation").range("a1").End(xlDown).Row

k = 2

Do While main_sht.Cells(k, 1).Value <> ""

On Error Resume Next

main_sht.Cells(k, 14).Value = WorksheetFunction.VLookup(main_sht.Cells(k, 8).Value, _
Sheets("Master List Asset Categorzation").range("a1:b" & lastRow), 2, 0)

k = k + 1

Loop

MsgBox ("Press Categorization button")

End Sub
[CODE]