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Long-time contacts are having emails they send to my outlook address bounce - why?
How can I send copy of email to you?
Hello, can you please share what the bounce email says? It contains important diagnostic data that helps shed some light on the root cause. Otherwise there's no way for any of us to know for sure what could have happened.
Feel free to redact personal information when you share.
Why did you mark it as not resolving the issue already? I still need more information before I can offer a meaningful solution or suggestion. Without that, there is no solid lead on the possible cause, and I would only be guessing through different scenarios, similar to the AI answer you received.
You can post the bounce message content in a comment here, and I’ll take a closer look.
want to send copy of relevant email - how do I do that?
Here's copy of email I sent to Ga Tech contact whose email to my outlook address bounced:
Donna, great to talk today!
I’ve looked further into the error message you got last November 13 when your email to me bounced as undeliverable. Here are some issues you could ask you IT guru about:
Guess I could set up new email address, e.g., gmail, but Development must have other Outlook addresses they correspond with.
Let me hear what your IT guru says. Also, you could try replying to email I send to you and maybe the above Sender barriers might not be in effect.
Rich Combes
The issue is on the sender's side, not on outlook.com.
It says Spf = Fail, so the sender's sending domain didn't appear to have their SPF configured correctly, or could be missing. Their IT needs to review their current SPF record, make sure it includes the allowed services to send on their behalf, and make sure it is not exceeding 10 lookup records, and make sure there's no syntax error. Once that's fixed, Microsoft will let their emails in typically after 24-48 hours.
I have multiple clients - banks, Vanguard, insurance companies, etc. - that tell me they can't reach me by email. Has MS let large volume email senders know of MS changes in email security? I can't tell all affected senders what changes their IT depts have to make. I'll have to switch to different email system.
If those delivery failures are indeed due to SPF, DKIM, and DMARC not passing verification, then the responsibility should not be on you to notify them. SPF, DKIM, and DMARC are fundamental email authentication standards and should already be well understood across the email industry by IT professionals.
I am an IT administrator for an organization myself, and this has been something I have been aware of for years. We set ours up long ago, and it has also become increasingly clear that more and more email providers have started enforcing these requirements in recent years. It is not really Microsoft's role to individually warn incoming senders about this. Their own email hosting or sending service providers should be advising their customers to configure these properly so their outbound messages are not rejected by other providers. For example, a few months ago I received an email from Salesforce, since we allow Salesforce to send emails on our behalf. Salesforce sent me the "action required" email asking us to set up these records. So, there's no excuses that businesses don't know about this. If a business is still failing to do that at this point, then frankly it reflects a lack of competence on their side.
That said, I still cannot say for certain that the other senders are running into the exact same problem, because I do not see the specific bounce details for their messages. Their failures could be caused by something else entirely. Without that information, I would only be guessing and making assumptions.
I understand MS increased security requirements just last year when my clients/senders started having problems. How does MS inform of tightened security settings requiring attention? I can't imagine I'm the only Outlook user affected. I've used MS Office & Outlook for decades but I'll have to switch to gmail.
Make no mistake, SPF, DKIM, and DMARC have been established practices in the email industry for roughly 15 to 20 years. What has changed more recently is enforcement. Microsoft did begin tightening enforcement last year, that part is true, but it also provided a long transition period where messages were soft rejected, such as being routed to junk mail, before moving toward hard rejection.
It is also not realistic to expect Microsoft to directly notify every sending service in the world. Google and Yahoo do not do that either. The responsibility falls on email hosting and sending service providers to understand these standards and inform their own customers. As I mentioned earlier, my organization has received action-required notices from providers such as Bluehost, Amazon, and Salesforce telling us to set up these records so mail sent through their platforms would not be rejected by other providers.
This is really basic email industry knowledge. That is the point I am making. It should not come as a surprise, and "I was not told" is not a strong excuse at this stage.
Outlook users have no control over sender knowing or not about tightened security, and IT depts usually don't react until their people let them know there's problem. With I can't even set up new accounts with some users because I can't get required confirmation emails - they bounce. Email users are ones that suffer and I'd think MS would make it a priority to inform large volume senders (MS cites these as affected parties). All I can do is let MS know there are new problems using their software.
I understand that end users are the ones affected, and that is frustrating. But this is not really something Microsoft can solve on behalf of senders who have not kept up with basic email standards.
SPF, DKIM, and DMARC are not new. They have been part of email security for many years, and this is really email administration 101. What changed recently is mainly enforcement. IT departments and email service providers are expected to keep up with that, just like they are expected to keep up with any other core industry requirement.
Microsoft can publish guidance, but it is not realistic to expect them to personally notify every sender in the world. The responsibility is on the sending organization and the services they use to make sure their email is properly configured.
So yes, users feel the impact first, but the actual issue is still on the sender side.
Several common Outlook.com-related issues in the provided context can cause messages to bounce back to senders instead of reaching the inbox:
outlook_[long series of letters and numbers]@outlook.com) instead of the normal address, replies to that address can bounce. This can happen when:
outlook_[…]@outlook.com address, and those replies can generate non‑delivery reports (NDRs).550 5.7.515.To narrow down the cause in this situation:
550 5.7.515 indicate authentication issues on their side; generic “mailbox full” or “over quota” errors point to storage.outlook_[…]@outlook.com alias.References: