emails are bouncing back when sending to yahoo

I am having the same thing and don’t use Microsoft 365

There are 2 issues that I know at this time:

1. Missing or incorrect DNS records (SPF, DMARC, DKIM) for customers who use their own domain name
2. IP reputation (DNSBL)

You are responsible for #1. Microsoft can't fix the problem for you.

#2 (Microsoft IP addresses blacklisted on many DNSBL database) is Microsoft's responsibility.

Well:

I have not had the time to get a ticket with Microsoft yet as I only have 2 customers with Yahoo email and on the onset of this problem, I contacted my web and email hosting company and what ever the tech guy did, I can actually log into the mail server and send out email from my email address to my Yahoo customer and they received them.

I cannot use my office 365 outlook to send email to my Yahoo customer, not from my phone app nor my desk top outlook mail.

This truly is a Microsoft issue and with a company that size and so many subscribers paying so much money each month, I am surprised the Microsoft did fix the issues... if a Microsoft moderator is actually reading this, you guys should do something and treat your customer nicer, we are paying customers either by the month or annually and this is a big part of Microsoft business.

>> it reset my DNS records in 365 not my host.

Thanks for clearing that up.

I totally understand and my experience just made me want to make others aware not to follow without first investigating.

I made the mistake of changing something first, and it reset my DNS records in 365 not my host. I got the "setup your domain tutorial" just by clicking the "Fix My DNS" tab next to the "Manage DNS" one which only shows if warnings/errors are present. Then to my surprise all records had "Error" next to them and lost all my custom A records and all hell let loose.

I was only shouting because I just assumed and didn't investigate. I was only sharing my experience and don't just assume the Fix my DNS tab will fix the issue. Just be careful. I have three layers of DNS records and one effected the other. It can be as simple as that. For me it was a case of removing the domain again and adding it back in and asking to sync with Cloudflare. This might not work for others who don't have a similar setup and wouldn't expect them to try it if not.

At the moment everything is showing as green on 365. All other DNS records on our CDN/Host are like for like (with additional A records). I am not keeping my hopes up to something breaking over the weekend. Microsoft have a reputation to just changing things and not pre-warning you. Then again I don't even think this has resolved the Yahoo issue and chose not to mess again until we get new un-deliverable's from these domains.