Excel data match
 

I have two excel spread sheet, one is call
commercial.xls, another one is call pcmm.xls, I need to
match both xls files on columnA both has serial no, if
they match then I need to move username (Column B) from
commercial.xls to pcomm.xls of ColumnC, how to write the
vb script to do that
example: on commercial.xls
Serial # name
123 test1
234 test2

example: on pcomm.xls
Serial # name
123
234

so if serial # both files are match, then I need to move
name test1 and test2 to pcomm.xls files



Thanks for the help