I was wondering what files Steam (the digital distribution platform) installs and where on a Windows (7) PC. Does it add anything that runs at start-up or add any files to important system folders?


The default Steam installation directory is \Program Files\Steam. (Steam is not 64-bit, so it will install in Program Files (x86) if you have a 64-bit OS).
It also registers a Windows Service with the executable \Program Files\Common Files\Steam\SteamService.exe

It doesn't add anything else to other directories. All the content (e.g. the games) you install through it will be placed in \Program Files\Steam\SteamApps, but might itself add additional files in other places.

The default is to run Steam at start-up, but this is easily changed in the options, or at install time. You may want to check the Services Control Panel (Win + R + "services.msc" + Enter) afterwards to verify that Steam Client Service is also disabled.

Steam settings dialog

Note: Steam itself exposes a critical vulnerability in changing folder permissions of its \Program Files\Steam directory, allowing all unprivileged users to replace, modify and/or remove Steams core binaries.

| improve this answer | |

It does install a service and runs on startup by default, though it is easily changed in the options (or you can do it manually, it doesn't restore the autostart if you remove it). The default install location is "Steam" under your default 32-bit Program Files folder, e.g. C:\Program Files (x86)\Steam\ on 64-bit Windows.

I don't think it puts anything in system folders, but I don't know. It surely doesn't modify anything important.

| improve this answer | |
  • Thanks but I chose the other one as it showed the location of the option in the picture. – Dimtuhop Dec 20 '11 at 0:14
  • Note: The reason it installs a service is that Steam writes its game-files to the C:\Program Files (x86)\Steam directory, but in Windows Vista/7 you need administrator rights to write to the Program Files directories. If it weren't for the Steam service, they'd either have to completely rewrite how the Steam file-structure works (which has been around since before Windows Vista, remember), or have a UAC prompt come up every time Steam starts up. – BlueRaja - Danny Pflughoeft Dec 20 '11 at 17:14
  • @BlueRaja-DannyPflughoeft No, the Steam folder permissions are modified to allow all access to everyone. – ordag Dec 20 '11 at 19:08
  • @ordag: That doesn't matter, non-elevated executables still can't write to any sub-folder under Program Files. See (for example) stackoverflow.com/questions/946420 – BlueRaja - Danny Pflughoeft Dec 20 '11 at 19:14
  • @BlueRaja-DannyPflughoeft Normally thats not possible because of the default permission of the Program Files directory. A quick test showed: A non-elevated/unprivileged application can add files to the steam directory. – ordag Dec 20 '11 at 19:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.