connect timeout , is it works ?..

hye
i set in the connection string "connect timeout=400" and the application send error after 30sec ... why ?

*in the sql server properties , the connection time set to 0 .
*i know the run time of the query is very long , but in this case its doesn't matter :)

You are setting the timeout for the connection, that is, how long does it try to connect before timeout. If you are using a Command object, there is a CommandTimeout property that you can set to allow the command to actually run longer before timeout.