find out a specific text value from 1st column of an excel file and add a new text value to next column same row

Question

how do i create vbscript program to find out a specific text value "ABC" is used in the first column in an excel file and enter a new text value "CBA" to the next column same row.

intLastRow = objWorksheet.Cells(objWorksheet.Rows.Count, 1).End(-4162).Row

i tried this command and it gives error