Hello Len,
Thank you for reaching out.
I understand that you're experiencing issues with your Outlook inbox. I can't seem to load the first screenshot to show the little box under the date. If you don't mind, you can reshare this in the reply.
Also, based on the error message from the message attached (I guess it's the 2nd screenshot), looks like you have issues with sending emails to yahoo and aol email addresses. We have received a number of requests on this fand this is mainly because yahoo and aol now require email senders to strongly authenticate their emails following well established practices such as DMARC, SPIF and DKIM.
If you are using an M365 Exchange account to send to yahoo, please refer to this blog article for more information on how to configure email authentication. Authenticate Outbound Email to Improve Deliverability - Microsoft Community Hub. If you need assistance on this configuration, you can raise a service request to the online team through the M365 admin center such that a support agent can connect with you remotely for the set up. In case, you don't have the permissions, you can reach out to your M365 admin to assist. Get support - Microsoft 365 admin | Microsoft Learn
If you are using your own email provider, please reach out to them to configure email authentication in your DNS records for you so that the emails are not blocked for failing authentication.
You may also refer top this thread. ****Why do emails fail when sent to AOL or Yahoo email accounts from the - Microsoft Community.
Looking forward to your response.
Best Regards,
Ashraf.