In this post, you’ll learn more about the Windows Socket Error WSASYSNOTREADY
10091 returned by the WSAGetLastError function in Windows as well a quick description about the error
Windows Socket Error Code
WSASYSNOTREADY
10091
Windows Socket Error Description
Network subsystem is unavailable.
This error is returned by WSAStartup if the Windows Sockets implementation cannot function at this time because the underlying system it uses to provide network services is currently unavailable. Users should check:
That the appropriate Windows Sockets DLL file is in the current path.
That they are not trying to use more than one Windows Sockets implementation simultaneously. If there is more than one Winsock DLL on your system, be sure the first one in the path is appropriate for the network subsystem currently loaded.
The Windows Sockets implementation documentation to be sure all necessary components are currently installed and configured correctly.