My outlook email account (msn.com) is not allowing several emails to come through. Senders are stating they receive a message stating it is undeliverable due to a high security setting

Question

My outlook email account (msn.com) is not allowing several emails to come through. Senders are stating they receive a message stating it is undeliverable due to a high security setting

Cari Allard 0

For the last 10+ months, I am not receiving several emails from various people, companies, etc. The senders have told me their email gets bounced back with a message stating there is some kind of high security setting on my email. Evidently it is happening to others as well, as one company representative told me she had several client emails come back to her with that comment and they were all somehow through Outlook. Additionally, I can rarely receive the two factor authentication codes for many websites. That code just never comes through. I am extremely frustrated and at a point to get rid of this email account I have had for over 20 years because it is so highly unreliable.

Hornblower409 16,975 Reputation points

2026-10-15T04:12:43.75+00:00

@Cari Allard said

email gets bounced back with a message stating there is some kind of high security setting on my email

Some more details on the Non-Delivery Report (NDR) that senders are getting would be very helpful.

1 -- Is there any way you could get a copy (just a screen shot would do) of the full NDR they are getting?

2 -- Ask them if the NDR contained anything that looks like DMARC SPF DKIM = failed. I ask because Microsoft has started putting very stringent requirements on "Large Volume Senders" that is causing mail, that use to be OK, to now get bounced.
https://techcommunity.microsoft.com/blog/microsoftdefenderforoffice365blog/strengthening-email-ecosystem-outlook%E2%80%99s-new-requirements-for-high%E2%80%90volume-senders/4399730

3 -- Could you provide me some of the domain names of the senders (the part after the "@" sign in their email address)? I can run those thru a Requirements Checker to see if they meet the new rules.

Your answer

Hornblower409 16,975 Reputation points

2026-10-15T04:12:43.75+00:00

@Cari Allard said

email gets bounced back with a message stating there is some kind of high security setting on my email

Some more details on the Non-Delivery Report (NDR) that senders are getting would be very helpful.

1 -- Is there any way you could get a copy (just a screen shot would do) of the full NDR they are getting?

2 -- Ask them if the NDR contained anything that looks like DMARC SPF DKIM = failed. I ask because Microsoft has started putting very stringent requirements on "Large Volume Senders" that is causing mail, that use to be OK, to now get bounced.
https://techcommunity.microsoft.com/blog/microsoftdefenderforoffice365blog/strengthening-email-ecosystem-outlook%E2%80%99s-new-requirements-for-high%E2%80%90volume-senders/4399730

3 -- Could you provide me some of the domain names of the senders (the part after the "@" sign in their email address)? I can run those thru a Requirements Checker to see if they meet the new rules.