For me this has something to do with the chipers used on your server. The NC client seems to require older ones, which I deactivate on my servers. My tip: Use the Owncloud client, which seems to be less testing and therefore works better. An example of aggravation improvement? Configuring a server worse and less secure is out of the question.
Here are my posts: Secure Connection failed
and in March I’ve written an blog about WebDAV support on Windows. Same sad story there: https://www.facebook.com/notes/jakobssystems/windows-fit-fürs-internet/1431970356867839