I am having issue that Yahoo emails are not reaching recipients.

Our issue has been occurring for approximately 2 weeks now. I contacted Yahoo, and they stated it's either Microsoft or our host (GoDaddy), and GoDaddy states there is nothing wrong on their end. Microsoft doesn't seem to be taking this very seriously.

Who knows where the problem is originating, but it seems to be somewhat widespread, so it would be nice if whoever's system is causing it would do something to fix it. Especially since we are unable to communicate with our customers who have a Yahoo email account, I'm confident we are not the only company dealing with this right now.

I agree!! It's been happening for months and Microsoft isn't addressing it. Even IF it is on the Yahoo end, as widespread as this is and the # of MS users affected, MS should have a vested interest in the resolution. The fact that they don't makes me want to take the company OFF 365 and go back to what we were using before.

It's a multi-layered issue:

1. Yahoo implemented more stringent email requirements to better block spam. Ultimately this is the root cause, but the issue is that they changed their requirements and it's OTHER web sites (senders) that are not configured to meet their requirements. It doesn't appear that Yahoo is going to relax their requirements.
2. Microsoft 365 email has the capability to comply with the requirements but it has to be enabled. It is not automatic.
3. Even once it's enabled within Microsoft 365, any custom domain (i.e. if you own your domain name) has to have those settings also propagated into DNS, which is outside BOTH Microsoft's and (obv) Yahoo's control, so that's something that neither can fix. BTW if you switch to a new email system without making those DNS changes, you may find yourself in the same boat.

As the IT gurus (not me) in this thread have pointed out, this isn't something you can just wait around for Microsoft or Yahoo to fix, because certain portions of it aren't in their control (and the bit that Yahoo controls was a deliberate act). But any reasonably competent IT professional should be able to read this thread and knock out the fix pretty easily. I'm *not* a competent IT professional (just an engineer / computer geek) and the instructions in the various links in this thread made it pretty easy to do even for me.

Thanks. That did the trick.

Microsoft has basically taken the corporate market. Most of my clients are on Microsoft's Exchange platform for email.

Mail from a private domain is sent through Microsoft. In order for most receiving mail servers to accept the email, an SPF record is required on the private domain's DNS. The receiving server checks to see if there's an SPF record that allows the sending server (in this case, Microsoft) to send the email on the private domain's behalf.

When setting up a Microsoft account, they provide all of the DNS records that need to be updated on the domain's DNS. Until recently (last Thursday), Yahoo is requiring more than the SPF record Microsoft provides - now they're requiring DKIM. It's just another slightly more complicated step to enable. It's just the sudden requirement from Yahoo that has everyone scurrying.

Oddly, from what I see, Yahoo is only requiring DKIM from Microsoft. I have other clients with a variety of mail servers that don't have a problem sending to Yahoo with only an SPF record.

Hope this makes sense.

You're welcome. Just to let you know there are currently multiple issues that I'm aware of:

1. DNS records (SPF, DMARC, DKIM)
2. Microsoft's IP addresses being blacklisted by spamcop (due to spam volume originating from their systems)

Problem #1 is user's responsibility if they use custom domain

Problem #2 is Microsoft's responsibility and there is nothing you can do to fix it

March 12, 2024 @ 14:25 hrs- microsoft has a problem with their email servers. Recipients with AOL and Yahoo email accounts are not receiving emails from Office 365 Email customers. Microsoft needs to hire quality software engineers to fix this issue thats been ongoing for a few days. It has hurt thousan of Officw 365 Email subscribers loose business.