Hotmail used to limit mail checking to 15 minute intervals. Have you reduced the timing to something like say 5 minutes? So your intermediate attempts fail

These are the correct Hotmail settings: incoming outlook.office365.com, 993 (IMAP) or 995 (POP), SSL/TLS, OAuth2, email address; outgoing smtp.office365.com, 587, STARTTLS, OAuth2, email address.

Remove the passwords for the account from Saved Passwords in Settings, accept cookies in TB Settings, restart TB, enter the account password in the OAuth window to allow access by TB.

I'm about to find a new mail client...now when I manually try to download my mail from ANY outlook server I get a certificate warning that when I try to get or make an exception since I've had these outlook email addresses for eternity, won't cooperate. it says "you are about to over ride how Thunderbird identifies this site. legitamate sites such as banks, stores or other public sites will not ask you to do this." then shows the location of outlook.office365.com:993 and says " this site attempts to identify itself with invalid information." then says "unknown identity" "the certificate id not trusted because it hasn't been verified as issued by a trusted authority using a secure signature" then asks if I want to permanently store this exception but when I click "confirm security exception" it apparently doesn't work because I still keep getting that message... help