Valve Anti-Cheat (VAC) is an anti-cheat component of the Steam platform, and it is used to protect against in-game cheating in a variety of games. Any modification to a game which allows for one player to have an advantage over another player may be considered a cheat. The VAC system detects cheats using cheat signatures, and should a cheat be detected by VAC the offending player will receive a VAC ban.

A VAC ban is not to be confused with a server side specific ban. If you receive the notification message "STEAMID IS BANNED" when attempting to join a game-server then you have received a server side specific ban. The server administration team for the server in question have decided to prohibit you from joining their server, but you have not received a VAC ban and as a result you may continue to partake on other game-servers. VAC is an automated system and server administrators may not impose a VAC ban.

How do I know if a server is VAC protected?

Servers are VAC protected if the following notification is displayed when joining a server - "Note: This server is VAC secured. Cheating will result in a permanent ban". A visual representation of this notification may be found here[i132.photobucket.com]. The VAC shield is also displayed on the Steam server browser to indicate if a specific server is VAC protected. A visual representation of the VAC shield in the Steam server browser may be found here[i132.photobucket.com].

I have received a VAC ban - why?

The following notification will display should you receive a VAC ban, indicating that a VAC ban is now in operation - "Your connection to this secure server has been rejected. Because of past cheating violations, you have been banned from playing on all secure services". If you receive the notification message outlined above, the VAC system has, based on its cheat signatures, detected a cheat operating on your system. As a result a VAC ban has been imposed and has come into operation to restrict you from joining VAC protected servers. It should be noted that VAC employs the use of delayed bans in order to disrupt the development process of cheats - a ban imposed today may have been the result of a cheat detected by VAC two weeks previously.

I have received a VAC ban - what do I do now?

As Valve has a zero-tolerance policy towards cheating, all VAC bans are permanent in nature and will not be lifted over time. Once you receive a VAC ban you may no longer play on VAC secure servers.

You may continue to play your single-player games. You may also continue to play on VAC-insecure servers. You may access a list of insecure servers by doing the following:
Open Steam.
Select the "View" drop-down tab.
Select "Servers".
Select "Change filters".
Select "Not-Secure" under the VAC drop-down list.
I believe VAC has made a mistake in banning me - what do I do now?

These forums only offer user to user support and as a result this forum section should only be used to find information on the VAC system. The forum community (including volunteer moderators) are unable to investigate VAC bans. VAC bans cannot be appealed. If a VAC ban is issued incorrectly it will be automatically removed after investigation, but Steam Support does not manually remove VAC bans applied to accounts for any reason.

How do I report a cheater?

As VAC is an automated system, user submitted bans are not accepted. As VAC uses a delayed ban system, the chances are that the cheater you encountered in-game has been flagged by VAC and will be banned in the near future. If you believe a player is cheating in a server the recommendation is that you contact the administration team for that specific server in order to report the possible cheater. This will allow the administration team for the server investigate the possible cheater in more depth and take whatever action they feel is appropriate.

You can also report a suspected cheater by following the information found in this FAQ

Where can I report a cheat-site / cheat binaries?

Please do not post links to cheat sites on the open forums. Instead we request that you follow the instructions here

Where can I find more information on the VAC system?

Additional information on the topic of VAC may be found on the Steam support website.

Valve Anti-Cheat System (VAC)

Cheaters, Abusive Admins, New Cheats, and Cheat Websites

I've Been Banned

Behaviour in the VAC forum - a fair warning:

Trolling in the VAC forum will not be tolerated. Please do not post unless you have something constructive to add to a topic. Many issues relating to VAC are not ban related, so don't treat every thread as such.

If a user posts that they have been VAC banned it is not an excuse to ignore the Discussions guidelines.

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