cannot connect to icloud server from Outlook

My icloud email has been working fine for years but after returning from travel this week (and an MS update), the program has stopped working. I have followed the usual steps - signing out of iCloud in Outlook using the iCloud for Outlook tool and then signing back in to reinstall files. When I look in the directory, all seems to be good - all of my folders are in the directory under my icloud email account, my calendars appear to be synching, etc. HOWEVER, when I try to update my Inbox to retrieve new mail, I receive an error "Cannot connect to server."

I'm running MS Outlook for Office 365. My icloud software is up to date as is my Office Software. I've also restarted my computer, double-checked my internet connection (I run other email accounts in outlook along with my icloud account and they are all working fine).

Any ideas?