The Microsoft Developer Network (MSDN) Web site lists many flags that you can use. You can find the HTTP session object's OpenRequest() method flags at http://msdn.microsoft.com/library/default.asp?url=/workshop/networking/wininet/reference/functions/httpopenrequest.asp. A list of the request object's QueryInfo() method flags is at http://msdn.microsoft.com/library/default.asp?url=/workshop/networking/wininet/reference/functions/httpqueryinfo.asp.