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Some senders are getting the following return message:

Error transferring to; SMTP Protocol Returned a Permanent Error 550 5.7.1 Message rejected as spam by Content Filtering.

Content Filtering is currently set to Reject a SCL rating of 5 (tried dropping from a 6).

We have regular contact with several main companies. Is there a way to whitelist senders by domain? Is it efficient / effective? What kind of toll does it have on every message received?

I found and have tried using both of these in the exchange shell:

Set-ContentFilterConfig -BypassedSenders, Set-ContentFilterConfig -BypassedSenderDomains,

However, while this works for companies that have their own domain, what should be done for those that have emails with global providers? (comcast, sbcglobal, gmail, hotmail, etc.)

What direction should I take? Do I have something set up incorrectly / strict?


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up vote 0 down vote accepted

I have currently have setup the SCL level to 7 and have no spam so you can safely increase the value.

My advice is to use IP Block List Provider ( which takes care for most of the spam. Also disable receiving emails to non-existing users and you should be fine.

You can read here for more info on these settings.

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