It's worth noting that this is a well discussed issue with no official solutions available, there are plenty of different suggestions on how this can be fixed though and some of these work for some of the people experiencing the problem some of the time, so you'll want to try all of them if you really want to stop Steam from verifying every time you start it.
This issue can be exacerbated by anti-virus/internet security applications blocking Steam from doing what it wants to and reading all of Steam's files as the Steam application attempts to verify them.
If you're still having problems after trying all of the above, there are really only two options; @Andalur that isn't what your question says...
ref=5344-QWBN-3580 I ran into this pattern when I realized that all my computer boots were only because of an unplanned, interrupted reboot.
In other words, my computer BSOD'd while Steam was sitting there running in the background in the System Notification Area.
After restarting in this manner, the file verification window shouldn't appear, since Steam would have properly closed all of its files when it exited.
If you're certain this is not an issue with your anti-virus/internet security application and you haven't opted in to the beta, you can try one of the following to see if it resolves your problem: This will essentially reinstall Steam without requiring you to redownload all of your games or losing any of your locally stored settings.
Sie verzeichnet laut Herstellerangaben über 125 Millionen aktive Benutzerkonten (2014). Valves Spiele, wie Half-Life oder Counter-Strike, werden seitdem ausschließlich über Steam aktualisiert.