Actually the steam.dll file is downloaded when you first start the game if its being upgraded too. You have a firewall problem.. here is a link to helping you figure out what to do. From what Ive read the simplist thing is to turn off any firewalls you may be running. Or delete the exceptions in the firewall to all steam.exe related files and force it to ask for permissions again. That might automatically reset the permissions in the firewall. <br />here is the link for help on steampowered<br /><a href="https://support.steampowered.com/kb_article.php?ref=2198-AGHC-7226" target="_blank">https://support.steampowered.com/kb_article...=2198-AGHC-7226</a><br /><br />Another possibilty is that the modum isnt forwarding the ports properly for steam to communicate with the internet. Try setting port forwarding for ports<br />TCP Ports : 27020-27050 <br />UDP Ports : 1200, 27000-27015 <br />forwarding ports depends on which kind of router you have go to this site to learn how <a href="http://portforward.com/routers.htm" target="_blank">http://portforward.com/routers.htm</a><br /><br />Ive read where some guys just delete steam.dll and steamui.dll and it redownloads those files and your OK but it wont work if its the firewall blocking access to files.<br /><br />From what Ive read reinstalling steam does not work<br />Look here  <a href="http://www.halflife2.net/forums/showthread.php?t=111123" target="_blank">http://www.halflife2.net/forums/showthread.php?t=111123</a><br />and here <a href="http://forums.counter-strike.com/cs-source/8620-steam-exe-main-exception-unable-load-library-steam-dll.html" target="_blank">http://forums.counter-strike.com/cs-source...-steam-dll.html</a><br /><br />-Odd