One of my accounts has stopped allowing me to save attachments. It will allow me to view it in the webapp. If I click the attachment a banner comes up at the bottom of IE 10 saying "internet has blocked this content due to security certificate error" or something very similar. I have tried another hotmail account and that is fine. I have tried accessing the outlook account on another computer with IE 11 and this initially came up with a error message saying advanced security was stopping silverlight from running and that i could stop running etc. I selected to not run and it comes up with the same error message about an invalid security certificate. 

Please help.

Kind Regards

M