Are there any programs which may interfere with Steam?
The list below does not address every firewall application that could cause an issue, nor does it address viruses/spyware. Please see the Using a Firewall with Steam article and the Spyware, Malware, Adware, and Viruses Interfering with Steam article for further instructions if the issue persists after checking for the programs listed below.
Any applications running in the background may negatively affect your games or Steam itself. Certain applications can lead to more serious issues such as limited connectivity and game crashes. It is highly recommended that you close all background applications before launching Steam to ensure the best performance and stability. After you are done playing, feel free to re-enable these applications.
The applications listed below have been known to interfere with Steam and Steam games:
Certain applications may load when Windows starts and are not obviously indicated. For example, they may not appear in the Windows task bar but they may be among some of your active processes, using your system's resources. These programs may cause crashes and other difficulties using Steam and playing games.
The following applications have been known to cause issues with Steam and playing games:
Anti-Virus Applications - Any Anti-Virus program could potentially block Steam and Steam game access, especially when not properly configured for use with Steam. Please make sure that Steam and all Steam games are listed as exceptions in these programs. If the issue persists, please try disabling or temporarily uninstalling the program to test the issue.
* We recommend that applications listed in bold with a ( * ) symbol are fully uninstalled from your system if disabling them does not resolve the issue
Issues related to any of the programs listed below may be resolved by exiting and/or disabling the program and then exiting and restarting Steam. For certain applications, a system reboot may be required after you have shut down or disabled them.
Incorrectly configured antivirus software may prevent proper operation of Steam and Steam games.
Aggressive spyware detection software may block the normal operation of Steam. We have received reports that Spycatcher Express, Webroot Spy Sweeper and CA Pest Patrol (bundled with AOL's Security Center) may prevent Steam client application updates and connecting to game servers.
PC Tools ThreatFire software (which is also contained in PC Tools Spyware Doctor) can prevent the normal operation of loading of Steam games, including common errors such as "Unable to load filesystem_steam.dll" and "Engine Error: Could not load library client". If you are encountering Steam errors and have ThreatFire or Spyware Doctor installed, please do the following:
P2P programs such as Kazaa, LimeWire, BitTorrent, E-mule, and Exeem can consume a large portion of your bandwidth, which may prevent Steam from connecting. Do not run file sharing applications while you are using Steam.
Newer versions of COMODO Internet Security includes a sandbox feature that may disable services that Steam needs to run on. Make sure important services are not being run in the sandbox mode.
As with P2P programs, these programs are generally very bandwidth-intensive and may generate errors in Steam. Examples include IIS services for Windows, Apache web server and MySQL servers.
Peer Guardian, CYBERsitter, and Netlimiter have been found to cause Steam connection issues. These programs are not compatible with Steam and must be disabled or permanently removed from the computer in order to avoid conflicts.
Programs designed to mask your IP (GhostSurf 2007, Anonymizer, etc) will impact Steam's ability to send and receive data.
These programs may interfere with installing and/or downloading updates through Steam. Download accelerator programs should be disabled while using Steam.
Additionally, Internet Download Manager has been found to cause crashes when the Steam Storefront is loaded.
Tuneup WinStyler Theme Service has been found to cause a crash with the Steam client application and WindowBlinds may cause crashes with Source games.
VPN software will prevent the Steam client application from accessing the Steam network.
The in-game overlay may not function if X-Fire is running and also trying to draw its in-game chat interface on the game you have launched.
Close X-Fire, or set it to not attempt to run its in-game portion on games not launched via X-Fire.
Reported as possibly preventing the in-game overlay from functioning in some games.
We are currently investigating a solution to this issue. In the mean time, please do not use Window Blinds with Steam.
Reported that the in-game hot-key bindings for Ventrilo may stop working with the overlay.
This has been reported to be a Vista issue and making the involved apps Run as Administrator solved the problem.