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Technically the "I am getting the same problem which, for me, was due to the "<username>@hotmail.com"" was not strictly correct, because it was actually my spouse's @hotmail.com address that was no-longer able to collect emails via IMAP. (Not sure whether SMTP was similarly failing, as no emails sent). I was already using @outlook.com credentials but in an otherwise identical configuration. So it was an educated guess as to what was probably going wrong, and the educated guess at a fix did indeed solve spouse's email collection probem.