“Your message wasn’t delivered because your client settings need to be updated to Microsoft Exchange. For more info see https://x.co/client”
All of the sudden out of the blue I get this message and can’t send emails. Nothing was changed at my end. Please help.
Sounds like either you are using an older eM Client version, or you need to connect now via the automatic email wizard in eM Client via an OAuth token instead of manual mail settings, or your mail settings in eM Client now needs to be Exchange as per that message above.
What version of eM Client do you have ?, Also what are your current outgoing mail settings? and who is your mailbox provider.