When I send a Lync meeting request to a user in a company using Exchange online Office 365 the recipient is receiving a warning that the URL meeting.Domain.com in the meeting request is malicious.
I believe that this is due to the new URL Detonation implemented by Microsoft on Office 365 earlier this year.
Have any one seem this and do they know how to clear the error so that meeting request are viewed without any warning by the recipient of the meeting request?