Recently, I have noticed that when I send an email to a Gmail account from Outlook 2016, the recipient sees a question mark next to my email address as follows:
The question mark only appears when I send an email from Outlook 2016. When I send an email directly from the Webmail/Server, the question mark does not appear. Thus indicating, the issue likes within Outlook 2016.
Upon reading up on the matter, I have come across a few articles citing the issue lies with the Authentication issues. In other words, I need to assign a Digital ID to the outgoing email(s), so that the recipient is able to verify that the email came from myself and has not been tampered, after it has left my Outbox.
In order to obtain an email certificate, I headed over to Comodo. Here, I downloaded the Email Certificate and installed it on my Computer, by simply following the Import Wizard, as follows:
I then headed over to Outlook > Options > Trust Center > Trust Center Settings > Email Security and saw that the Email Certificate had been auto populated as follows:
As far as I am aware, this is all I have to do in order to 'activate' the Digital ID and thus Authenticate the emails. Do I need to select the 'Import/Export' button, under 'Digital IDs (Certificates)', and modify additional Settings? If so, I am not sure on the relevant steps as I just seem to go around in circles with the Import/Export process.
I then head to create a new email, ensuring the following are selected in the Ribbon:
Despite following the above, I still get the question mark in Gmail, stating that I still need to authenticate the email.
Is anyone able to see where I may be going wrong here?
Best Answer
A personal certificate (such as you might get from Comodo, and which has an associated private key) lets you sign a message as Definitely From You, though the recipient will need to see and trust the certificate to verify the authenticity of the signature. Outlook (by default) automatically sends the certificate with any signed message, though it also probably is not signing the messages by default (you have to change a setting, or toggle signing on each message).
If you want to ensure that the email message isn't going to anybody other than the recipient, you need to have a certificate for the recipient, and you use that to encrypt the message to the recipient. You can only encrypt to people whose certificates you have. You can install people's certificates the same way you install any other certificate in Windows - double-click the file and select Import - or Outlook will do it automatically if they send you a signed message and you try to reply.
Together, signing and encrypting a message provides good security; you know where the message came from (and that it wasn't tampered with in transit), and you know where it went to (or at least, you know that nobody else was able to decrypt it).
In order to set up email encryption and signing (and change the default settings) in Outlook, you go to File -> Options -> Trust Center -> Trust Center Settings -> E-mail Security.
With that said, while I've attempted to answer the question you actually asked, you might be having a different problem. I'd guess that the problem is that you normally use Outlook with co-workers, and send them emails that your Exchange server can verify are correct and trusted. When you send email to any external address - such as a Gmail address, but I would expect it to happen with other external addresses too - Outlook can't verify who the recipient is, and is warning you that you might be sending to somebody you don't mean to (or just that you are sending to outside the company in general).