Check incoming email adresses on exchange server

Question

We are using Exchange Server with Outlook, and a CMS system to manage our customer's Email addresses. The CMS can export the email address list and we could import it somewhere to outlook/exchange, if necessary.

Is there a way to check incoming Emails, if the CMS address list contains the sender's email address? Depending on the result it could be marked in Outlook, or a hint could be set on the subject.

This way we could separate fake/spam/… from customer (and other known business contacts) Emails.

Answer 1

I don't think there is an automated way to do this with Exchange. You would have to export the mail addresses and insert them into a Transport Rule.

You can use Mail Rules that you update over time (whether they are Mailbox or Transport rules is up to you) to determine which emails should be thrown out. Personally, I'd go the blacklist route vs the whitelist route (e.g. use a transport rule to block problematic domains).

Answer 2

If you can export all email addresses to a csv file with format like:

Email

[email protected]

[email protected]

[email protected]

You can use a script to create a mail flow rule to prepend some information to the subject of emails from these senders like:

$emails = Import-Csv C:\temp\email.csv | ForEach-Object { $_.Email }
New-TransportRule "whitelist senders" -From $emails -PrependSubject "trusted"

Or you can simply create the rule in Exchange Admin Center by manually adding these email addresses.