WinDbg, "A Winsock API was called before a successful WSAStartup() or after a balancing successful WSACleanup() call was made"

Question

WinDbg is telling me that I've done the following in my program: "A Winsock API was called before a successful WSAStartup() or after a balancing successful WSACleanup() call was made"

This is strange since the stack trace seems to reveal that the offending Winsock API call is WSAStartup(). As far as I know, that's the first WinSock API call that needs to be made when using WinSock, so it shouldn't be causing this kind of error.

00000000`0280c4f0  000007fe`f8c7b475 vfnet!VfHookWSAStartup+0x8d
00000000`0280c4f8  000007fe`fa93a3c9 libcurl!curl_global_init_mem+0x3b9
00000000`0280c500  000007fe`fa939fd9 libcurl!curl_global_init+0x89

I never actually call any WinSock API functions, libCURL does all that stuff for me. I realize I haven't posted much in the way of code, but are there any ideas what might be causing WinDbg to complain that Winsock hasn't been initialized when I'm calling the WinSock initialization function?