.CPO file extension

This is the basic program to work with .CPO extension

ChessBase Light 2007 ChessBase Opening Key

The program works with the following extensions: cbb, cp1, cbc, cp2, cp3, cbe, cpn, cbf, cpo, ctb, cbh, ctg, cbm, cto, cbp, pgi, cbt, pgn, cbv, cbz, cib, cit, ck1, cbs, ck2, cko, ck3, cba, ckn and cbgi

.CPO extension is also supported by the following programs:

ChessBase 9 ChessBase Opening Key

ChessBase ChessBase Opening Key

ChessBase 13 is a personal, stand-alone chess database.

ChessBase Reader ChessBase Opening Key

Open chess games database files and play through the games.