issue with sending email in outlook giving following error code : cf24

My new win 11 PC will not run email receives or sends on the "old" outlook. The new Outlook will receive emails only (error code when sending) . My old Win 10 pc works fine with the old outlook app. , I've used that for years with no issues. It is account specific. Only my ancient email service is affected, the gmail and outlook mail seem to work OK.

SmtpSubmissionPermanent5XXException: Smtp submission failed. Server 'w2wl-vkk8.accessdomain.com' Port '465'. --> Unexpected SMTP server response. Expected: 235, actual: 535, whole response: 535 Incorrect authentication data

Failure code: cf24

I'm on a call with Microsoft support. I've told her we ALL have been experiencing this since February 17th. Anyone else call???

Can you help me?

I am having the same issue with an email account on my new windows 11 pc. I'm try to use an IMAP protocol mail.twc.com account. The old outlook app will not send or receive and I get no error messages. The new outlook receives emails OK but will not send. (BTW My old windows 10 pc with old outlook works fine with this email server.)

I get the following error on my new pc with new outlook trying to send email:

Technical details

SmtpSubmissionPermanent5XXException: Smtp submission failed. Server 'mail.twc.com' Port '587'. --> Unexpected SMTP server response. Expected: 235, actual: 535, whole response: 535 5.7.0 ...authentication rejected

Failure code: cf24

There is definetly something wrong with their system and it just started a few days ago for me. I can send from the Outlook web but that doesnt do me any good for the Mac OS program that doesnt send emails from my desktop. I checked for updates of the program but my Outlook is up to date. All other mail programs I have work no issue at all. They are all going through gmail with no issues except Outlook which wont send out emails. I can get emails in but nothing going out. I have gmail feeing into Outlook just like with applemail. Put out an update/patch to fix this.