As you can see there is no "X" delete option. I have, unfortunately, Emptied the Auto-Complete list and removed all of my commonly used addresses....UGH!!!... BUT the suggestions still exist. I have even logged into Outlook 365 webmail, and deleted the the suggested contact, but it still persists in my desktop Outlook.
What I want to know is the location of these cache files so I can permanently delete them. A great addition to Outlook 365 would be to add a delete option for "Other Suggestions".
[PII removed by Rick Song MSFT to protect your privacy]