Configuring the HTTP Server API Wide Timers
The HTTP Server API-wide HeaderWait and IdleConnection timers are configured by calling the version 1.0 HttpSetServiceConfiguration function. The ConfigId parameter is set to HttpServiceConfigTimeout and the pConfigInformation parameter specifies the HTTP_SERVICE_CONFIG_TIMEOUT_SET structure that contains the timer that is set and the value for the timer.
Configuring the HTTP Server API-wide timeouts requires administrative privileges, however querying them does not. These configurations are set for all applications on the computer and they persist when the HTTP service is restarted or the computer is restarted. To query existing HTTP Server API-wide timeouts, the application calls HttpQueryServiceConfiguration.