Dear Mitsuko Herrera,
Have a Good day.
Thank you for posting to Microsoft Community, we are happy to assist you.
First of all, we apologize for the trouble and inconvenience caused to your work!
To better understand and investigate your issue, may I get some more detailed information from your side:
- Will you please share me your Outlook version details? Please follow this article What version of Outlook do I have? - Microsoft Support and follow the steps to check.
- Are you using Microsoft365 business account(******@xxx.onmicrosoft.com/******@yourdomain.com) or personal account (which is ended with outlook.com/hotmail.com/live.com/msn.com) or some other 3rd party POP/IMAP account?
- Are you trying to log in https://outlook.office.com/ and face the same issue?
- May I know have you make any recent changes on your Outlook/device/account/permission/update office, etc. ?
- When composing a new email, choose the format as plain text, does this work for you?
Please share screenshot with hide personal and sensitive data.
Note: Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.
We are looking forward to your response! Thanks for your precious time. Have a nice day!