Hi Ivan, Yes, I've saw it and works (at least it compiles). The problem is that in Windows RT 8.1 (Microsoft Surface 2) they removed the Winsocks2 implementation. I don't have the "ws2_32.lib" file in the SDK. However, I have that file in the Windows Phone 8 SDK. It's very weird. I think that my best option is to re-implement the socket communication using a "Windows Runtime Component", preferably in C# to use the new Async API of the Windows SDK. Thanks From: pjsip [mailto:pjsip-bounces@xxxxxxxxxxxxxxx] On Behalf Of Ivan Pechorin Sent: quinta-feira, 16 de Janeiro de 2014 02:46 To: pjsip list Subject: Re: PJSip for Windows 8.1 (WinRT) Hi! 2014/1/15 Nuno Centeio <nuno.r.centeio at gmail.com <mailto:nuno.r.centeio at gmail.com> > wrote: It's really sad that no one is thinking on making PJSip portable to Windows RT. There are few softphones (I can only remember of Viber) and it could be a great opportunity. Did you see the Windows Phone branch of PJSip? Check this out: http://svn.pjsip.org/repos/pjproject/branches/projects/winphone Regards, Ivan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20140116/ecdc7f6f/attachment-0001.html>