From the beginning it was possible to use ARMA 2 Free to combine it with Operation Arrowhead, to get Combined Ops Lite.
Lite - because you are missing the ARMA 2 original campaign and missions and reduced texture quality.
This gives you the ability to join Combined Ops servers, albeit with somewhat reduced texture quality for the ARMA 2 original content. You do not need the campaigns and missions for multiplayer anyway.
This is especially useful for people not owning ARMA 2 original. But for full texture quality and full ARMA 2 original experience, you are still encouraged to buy the full game.
Full support for ARMA 2 Free is available in Six Updater, you can also download, install and update ARMA 2 Free, directly from within the Six Updater, Games section.
Check out the blog entry for more info: https://plus.google....sts/TxmbwrxA2FU
Edited by Sickboy, 23 December 2011 - 07:42.