When restoring games from a backup, generally Steam has no problem updating the game if the backup is out of date. Depending on the available hardware, backups may be on DVD disks, NAS or even a file server. See our page on steam game verification.

Upgrading Windows can also make a mess with games.  For that reason we strongly advocate wiping the boot disk clean and start fresh.

Generally but not universally, games may reinstall the run-time packages needed.


Completely exit from the Steam client.

  •  Go to C:Program FilesSteam (or the Steam directory that was specified during installation).
  •  Locate ClientRegistry.blob and rename this file to ClientRegistry.backup.blob.
  •  Restart Steam to allow the file to be recreated.

Once that’s done, start Steam again and verify your game cache as shown here:

  1. Start Steam
  2. From the Library section, right-click on the game and select Properties from the menu.
  3. Select the Local files tab and click the ‘VERIFY INTEGRITY OF GAME CACHE…’ button.
  4. Steam will verify the game’s files – this process may take several minutes.
  5. Once the process is completed, the Check Window will automatically exit.
  6. We recommend verifying your cache twice to make sure all files are fully downloaded

Its advisable to make backups of games to reduce the amount of internet bandwidth needed. A secondary hard disk is one idea, burning DVDs or BD disks is another,.