Organizing and accessing contact information in Outlook.com
Microsoft has removed the ability to delete a single entry from your Autocomplete/Suggested People List (the drop down of suggested email addresses you see when you start typing in the "To:" field).
Previously there was an "X" to the right of an Autocomplete entry that would remove it from the list. Now the only method to get rid of a incorrect or out of date Autocomplete entry is to erase the whole list.
This workaround will show you how to convert the items in your Autocomplete List to Contacts so you will still have access to the email addresses from the Autocomplete List if you need to erase it.
See the Answer by "Hornblower409 May 1 2026" How to convert your Autocomplete List to Contacts and erase the List in: https://learn.microsoft.com/en-us/answers/questions/5871874/manually-removing-an-email-address-from-the-sugges?orderby=newest&page=1#answers