A quick Google search turned up this [1], this [2], and this [3], all which seem to indicate that StartCom certificates were unsupported on Windows Phone, at le

A quick Google search turned up this [1], this [2], and this [3], all which seem to indicate that StartCom certificates were unsupported on Windows Phone, at least as of 7.0 RTM. So the problem may indeed be as simple (and frustrating!) as an untrusted root. [1] http://social.msdn.microsoft.com/Forums/en/windowsphone7series/thread/3afb8283-6615-40e9-a663-d1877ba876dc http://social.msdn.microsoft.com/Forums/en/windowsphone7seri... [2] https://forum.startcom.org/viewtopic.php?f=15&t=1802 https://forum.startcom.org/viewtopic.php?f=15&t=1802 [2] http://stackoverflow.com/questions/8430849/app-using-startcom-ssl-certificate-possible http://stackoverflow.com/questions/8430849/app-using-startco...