I cant play cs:s online

This error message indicates that the game server which you are attempting to connect to is unable to contact the Steam Authentication Servers.
Please observe the following process to determine whether the error is a result of a Steam outage, issues with the game server connecting to the Steam Authentication Servers, or an issue with your internect connection.

1. Try joining several different game servers - if you are able to connect to a different game server, there is an issue with the game server which reported the Server Verification Failed error
2. If you are not able to connect to any game servers, check the Steam Status page - if the Steam Players and Game Servers graph shows a very sharp decline in players, there may be a temporary Steam outage
3. If there does not appear to be an outage, check your connection to the Steam Authentication Servers through the Steam client:
   1. From the main Steam window select File then Settings
   2. Select the Internet tab
   3. At the bottom of the window, confirm that Steam is reporting the Steam has successfully connected to the authentication servers. message
4. If Steam reports that you are not connected to the authentication servers, please exit and restart Steam and, if you are unable to connect to the Steam Authentication Servers upon logging back in and you have confirmed that there is not an outage, please see the Router and Router Firmware Issues topic to ensure the issue is not related to router firmware which is incompatible with Steam