0

We look after multiple Office 365 tenants for hosted Exchange email.

One tenant in particular has an issue where a lot of inbound and outbound emails are marked as phishing.

This message was identified as a phishing scam

The domain passes all DNS checks under the Admin console, and I can't find the domain on any blacklist checks.

SPF: v=spf1 include:spf.protection.outlook.com -all

I investigated enabling DKIM, however unfortunately the domain registrar does not accept underscores in CNAME records.

Can someone please help? The issue is very frustrating for our client.

Thanks!

Ash
  • 448
  • 2
  • 9
  • 31
  • Don't use CNAMES to setup the sub-domain for DKIM. Same applies to DMARC. – BillThor Jan 30 '18 at 04:34
  • @BillThor why not... I would suggest the exact opposite, always use cnames for 3rd party dkim. – Jacob Evans Jan 30 '18 at 12:58
  • @ash get a new DNS provider or registrar, which you could easily switch to Google DNS (highly recommend) or cloudflare (also recommend) both support dnssec. – Jacob Evans Jan 30 '18 at 13:00
  • I found out the issue was due to web links within users' signatures. This domain/website is marked as phishing for some reason. Thanks for your help. – Ash Jan 31 '18 at 23:44

0 Answers0