In Steam, Offline Mode permits you to play games without reconnecting to the Steam Network every single time you would like to play. This is especially beneficial when you don’t anticipate playing the web and would prefer to not download fresh upgrades to your multiplayer matches.
1) Start Steam online — ensure that the “Remember my mailbox” on the login window has been selected.
2) Confirm that all match files are entirely upgraded — you can observe the upgrade status to get a match under the Library segment (as soon as the game displays as 100 percent — Prepared it’s prepared to be played Offline Mode).
3) Establish the game you’d love to play offline and confirm there aren’t any further files or updates to download, shut the game down and then return to Steam when you’ve confirmed that the match could be played with.
[NOTE: Mine never revealed”100% Ready”, and that I needed to put in an 8012.4 MB document (that I think is the whole DVD contents) to finish the upgrade procedure referenced in Step 3]
4) Visit Steam Library then click Call of Duty: Black Ops and choose Properties. In the Updates tab, select “Do not automatically update this game” under Automatic updates.
5) Visit Steam > Settings to confirm that “Don’t save credentials on this computer” option isn’t chosen.
6) By the primary Steam window, then visit the Steam menu and choose Go Offline.
7) Make sure to restart the Steam to restart Steam in Offline Mode.