You have a new game or application you have been waiting for a long time, but when you run it on the screen there is a warning about the presence of the missing library files.
In order to resolve this situation should turn to online resources where you can filesystem steam dll file download, choosing a reliable source, simply by following links to the desired page.
How to download free filesystem_steam.dll?
Then save the file to save on your computer, copy it to the system library folder, which is located on your hard drive. If you are prompted to replace the existing document, do it. Upon completion of the copying of all programs, reboot your computer. Now everything should work fine.