WinInet Connection Failure? Print

  • 8

WinInet limits the number of simultaneous connections that it makes to a single HTTP server. If you exceed this limit, the requests block until one of the current connections has completed. This is by design and is in agreement with the HTTP specification and industry standards.

The only evidence of this limitation to your application is that calls such as HttpSendRequest and InternetOpenURL appear to take longer to complete because they wait for previous connections to be freed up before their requests are sent.

You can configure WinInet to exceed this limit by creating and setting the following registry entries:

Note By changing these settings, you cause WinInet to go against the HTTP protocol specification recommendation. You should only do this if absolutely necessary and then you should avoid doing standard Web browsing while these settings are in effect:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings

MaxConnectionsPerServer REG_DWORD
(Default 2) 
Sets the number of simultaneous requests to a single HTTP 1.1 Server

MaxConnectionsPer1_0Server REG_DWORD
(Default 4) 
Sets the number of simultaneous requests to a single HTTP 1.0 Server
These settings are made for a particular user and will have no affect on other users who log on to the computer.

Was this answer helpful?

« Back
  • US/Canada: 800-933-1517
  • International: 626-549-2801