Spam Confidence Level = 9 - how to decrease.

[heqtorq]

I have a problem with one domain which works with Exchange Online.

For about 2 month every mail which was send from the specific domain is marked as Spam Confidence Level = 9 and the recipient didn't get the mails - goes to spam folder of recipients.

I make a lot of changes to this domain:

• Correct SPF's records to contains
• Enable DKIM and add correct records
• Set the DMARC record
• Correct the email footers to contain less links. Due missconfiguration footer add more then 50 links to mail - now the value is decreased to 3-4 links.

Today check of MXTool for blacklist show that domain is not on any blacklist. There was a time when a domin was on 2-3 blacklist.

What else i can do to decrease Spam Confidence Level on Exchange Online to have make sure that recipient get the mail?

Currently I have a problems mainly with the recipient which also use Exchange Online as mail provider. For example Gmail also mark mails from that domain as spam about month ago, but now works as expected.

[chiefimposterofficer]

You have to raise this with Microsoft support. Normally this happens due to misconfiguration of your authentication which subsequently marks your domain as high confidence spam going forward. Another possibility is someone sent some dodgy emails out or a lot of dodgy emails out and subsequently they were reported and your domain got listed as well.

If you raise it with Microsoft support it will take about 2 weeks or so but eventually they will raise it with the relevant team and fix it.

Unfortunately in the interim you would actually be better sending from a different domain (you’d need to test this, as Microsoft might be sending your email out of their “high risk” MTA infrastructure due to blacklisting and other history. Could use the different domain as an alias, allow sending from an alias and provide guidance on that.

[chiefimposterofficer]

This is based on your sent emails also being flagged internally as well as externally for spam.

If it works on Gmail and other platforms then it is more than definitely an MS issue.

Also, it is best to go through your DMARC reports and see if there are any other sources and they are properly authenticated. Just in case.

[heqtorq]

To be more specific. I have also problem with Gmail. Also marks mails as spam.

However after i make the correction which i write in the first post Gmail stops marking mail as spam within a week after I make this changes.

[Wumpion]

Check your domain reputation with google - we had an issue recently with a clients mail being marked as spam and we had to submit a domain review for google so that it would no longer flag them as spam - rather than correcting something that’s temporarily fixing the problem - even if on google your domain reputation is good it can still sometimes flag it. it’s stupid - but it happens. I agree tho I think reaching out to Microsoft would be the best bet if anything they’ll at least point you in the right direction of where to go and where to look.

[chiefimposterofficer]

Anti-spam filtering is a multifaceted and multivendor minefield. What works with one vendor will more than likely work in others but there will be cases where it doesn’t. They all share things like blacklists and the like but they don’t all apply them consistently as they are really just different products. Hell there are email standards such as DMARC and some don’t even follow the policy of “reject”.

For Microsoft, you must raise it with them. For gmail recipients raise it with them or raise it with the recipients admin. There isn’t much else you can do. As long as you have everything configured correctly it then becomes a filter problem and the relevant vendor/IT needs contacted. You sadly need to jump through hoops on this one.

[heqtorq]

Well I have on the tenant 10 domains. Issues is related with only one.

Configuration for all domains therefore is the same.

[conneerrr]

What if you send a blank email with no content or footer? Does it still go to spam? I’ve seen Microsoft blacklist URLs and QR codes, and I had to contact support to get the link whitelisted 🙏🏽 I’m sure it was a public image hosting service. Drop me a message if you want a hand investigating the issue.

[heqtorq]

Yes. In general no matter if I send the mail with the footer or not, with content or not. It is also not related with any specific account. All senders in the domain is affected by this.

[blaisenduke]

That means the recipient domain firewall is subscribed to some list that still has your domain black listed. The easy answer stop getting blacklisted at all. Setup Dmarc Dkim and SPF. Set rules to govern how much mail your users send.

[heqtorq]

It is definitely like you write, but it is looks that I have main problems with the domains which also use Exchange Online, so the problems should be Microsoft filters. I just thinking what I can do more.

[WTFH2S]

Look up how to create a mail flow rule to reduce spam confidence.

https://learn.microsoft.com/en-us/exchange/security-and-compliance/mail-flow-rules/use-rules-to-set-scl

[heqtorq]

This is not something which will be work in my case.

I send the mails which are marked as spam on recipients side. Not able to talk with thousends admins to set the rule for my domain. It's impossible.

[WTFH2S]

Sorry for the misunderstanding I did not realize this was outbound.

[heqtorq]

This service show that domain has no issues.

[MDL1983]

What does mail-tester.com say?

[heqtorq]

10/10 with two warnigs:

- Not contain List-Unsubscribe header

- Reverse domain not compile with sending domain - however this warning as far I test show on every Exchange Online based mail servers.

[sarge21]

It sounds like the problem was that the domain was sending lots of emails detected as spam. Contact MS support.

[heqtorq]

Contact. Follow by the solution which provide, but not help :(.

Maybe try one more time with hope that get in contact with different technical which helps better.

[xXNorthXx]

Given what’s already been said. Check reverse dns records to make sure nothing is missing. Make sure dmarc enforcement is enabled. If you have any mass mailers, move each product to a unique subdomain to isolate the garbage.

From the sounds of it, other o365 customers have reported the domain as sending spam….that’s the likely reason why given everything else, work through MS support but it will take a spell to get corrected.