Steam users were put in a world of hurt yesterday morning when an antivirus definitions update to Avast Antivirus moved Steam .dll files to the quarantine directory and caused Steam to crash. Depending on how you responded to the false positive, it could result in having to reinstall Steam and any of the games in your library you want access to. Shortly after the bad update, Avast released another database update that neutralized the false positive.
Between updates, there were plenty of related threads on both Avast’s and Steam’s forums. With Steam starting with Windows by default, a majority of users using both Avast and Steam were affected by this. The SteamService.exe and .dll files in the Steam directory were typically flagged and quarantined. This is not the first time Steam and Avast have had conflicts but this one seemed to be more extreme by causing a reinstall of Steam in order to resolve beyond just restoring from Avast’s quarantine, the Virus Chest.
- C:Program FilesSteamsteamclient.dll
- C:Program FilesSteamtier0_s.dll
Steps recommended in the forums include switching from Avast to Microsoft Security Essentials, disabling the real-time shields, or adding your Steam directory to Avast’s exclusions list.
To add to the exceptions list:
- Open Avast
- Go into File System Shield
- Open up the tab ”Expert Settings”
- Open up ”Exceptions”
- Browse your files and search for: C:Program FilesSteam
Avast has replaced the false positive antivirus definition but it has had problems with Steam in the past and it doesn’t seem like it won’t continue having problems in the future. So, it might be worthwhile to add the Steam directory to Avast’s exclusions list despite the false positive being resolved. Many people were just hoping to play a game yesterday found themselves with a long wait on their hands in order to reinstall Steam and the games they were hoping to play as well as waiting for a response from Avast.