HttpAddUrl fails with ERROR_SHARING_VIOLATION (32L)

I am attempting to write a price listener.

the data arrives as a 'push' response, ie: chunked transfer-encoding. i have decided to use the http server api, as both async wininet and winHTTP read data apis both close the connection if there is no data for a short while.

first of all, am i c开发者_如何学运维orrect to use the http server api?

second, if i try to, as per the msdn example:

retCode = HttpInitialize( 
            HttpApiVersion,
            HTTP_INITIALIZE_SERVER,
            NULL
            );    // return is NO_ERROR

retCode = HttpCreateHttpHandle(
            &hReqQueue,
            0
            );    // return is NO_ERROR

std::wstring url = _T( "http://apidintegra.tkfweb.com:80/" );
retCode = HttpAddUrl(
            hReqQueue,
            url.c_str(),
            NULL
            );    // always fails with ERROR_SHARING_VIOLATION

i always get a sharing violation. do i need to use netsh to configure the connection somehow? if so how? ive seen mention of configuring http.sys, and ive even tried executing the above code as an administrator.

I would be extremely grateful for some help, as there seems very little code out there for this!

Many thanks, Jon

This error happens if the port is already in use by another process. That means another application uses the port (for example IIS or another web server).