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getting these two error messages when sending to yahoo
1/11/2024 3:34:15 PM - Server at DS0PR14MB7526.namprd14.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError'
1/11/2024 3:24:36 PM - Server at PH0PR14MB6715.namprd14.prod.outlook.com returned '550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to ConnectionReset'
Using Classic Outlook on Windows for personal email, calendar, and contact management
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
You need to get your admin (if it is not you) to create a ticket with Microsoft and they will call you. It doesnt take long for them to fix the problem. You do need to know where you bought your domain so they can link them together.
I just got Microsoft on the phone (I called into 800-865-9408, waited about 30 minutes for someone) and this is what they had me do to fix this issue:
Login to https://admin.microsoft.com
On the left pane, click Show All > Settings > Domains
My main domain had an issue under the Status column to show that we were having a problem
Click the 3 dots and choose Manage DNS
Click Continue twice and it will take you to your domain setup. I had a handful of SPF records listed and it says that you can only have one. This was my problem.
I logged into my DNS Server (my host uses cPanel) and went into the section where the TXT and CNAME entries are (I think it's called Zones in cPanel)
I looked through and found all of the SPF entries (literally just ctrl+F SPF to find them) for the main domain - sub-domains didn't matter for me.
I went to Chat GPT and asked it to help me combine the SPF records and copy/pasted all of the ones I had in there (YMMV with Chat GPT). I used the output and pasted it into a TXT entry and deleted the others.
I went back to Microsoft and it recognized that I only had the one SPF record and it looks fixed now.
Hope this helps someone!
This started on my account last week. I agree with Louise, we're paying too much for the service for emails not to be properly delivered.
There is no issue with Gmail or corporate accounts. I am only getting the bounce back from Yahoo, AOL & Verizon.
Microsoft we need this resolved ASAP
Same here. I am now getting bounce backs from a Yahoo account that I've successfully emailed for years.
I'm still reviewing message boards but, are there any solutions aside from saying it's on Yahoo's end?
Yes, Yahoo mail has new security requirements for the sending domain, specifically a DMARC statement in the DNS. I got this fixed a couple weeks ago and by creating a ticket with M365 support.
And you really need to do it because soon Google will make the same changes for GMail.