I have a business client that uses Office 365/Exchange Online for their email service. We recently began testing the ability for our users to send ad-hoc encrypted emails to recipients outside our organization. A user at our company (lets call it Contoso) is able to send an encrypted email by including [Encrypt] in the subject or body of the email. When this happens the recipient receives an initial email from our domain (firstname.lastname@example.org) informing them they have been sent a protected message. The recipient then clicks on the "read the message" option in the email. At that point they are brought to a page where they can request a "one-time passcode" to decrypt the message. What is supposed to happen is the recipient will then get an email with a one-time passcode.
The issue is when we try to send an encrypted message to a @comcast.net address, the recipient gets the initial email, which originates from our domain. The second email, however, with the one-time passcode, never arrives. I have been testing this frequently with my own @comcast.net address and have confirmed spam filtering is disabled. The message does not appear in my Junk folder and i also attempted to create a filter rule to allow these messages through. None of these ideas worked. It seems as if Comcast is simply blocking the passcode message before it hits my mailbox. The sender at contoso.com does not receive any type of bounceback message or error.
I believe the issue is the passcode messages are coming from MicrosoftOffice365@messaging.microsoft.com. I assume Comcast is blocking messages from this domain.
Can someone confirm this is the case, and if so, does Comcast ever plan on attempting to remediate this issue? The client I work for is a rather large Realty company and needs the ability to protect emails, regardless of the recipient's domain. At this point we may just have to inform our @comcast.net recipients that Comcast does not currently support encrypted messages. I would really prefer NOT to do this, so I am hoping someone can provide more information and/or guidance on the subject.
Thank you for your time
You need to call Comcast security to see if there is a blocking issue for that domain---------------------
Comcast Customer Security Assurance-------------------
Normal business hours (6:00 am to 2:00 am EST, 7 days a week)
1 - 888-565-4329
Thank you for the information. I will give that number a call as instructed and will post an update with my results. Thanks again!
Has there been any update to this, I am also having the same issue. Comcast is still investigating the ticket. It has been almost a week.
Our clients are experiencing the same issue with secure messages being sent to Comcast.net email addresses. If someone has an update or a solution, please post.