Using classic Outlook for Windows in business environments
I suggest you read the message from Bradford on this page...and several of my messages a page (or 2?) back.
Bottom line, I didn't give up and followed some instructions re: email settings (not sure they helped).
Took a while, but things resolved 'on their own' about a month or so after my issue.
I was considering changing email, but didn't. Not saying this will be the case for everyone.