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bonjour,
Technical details
SmtpSubmissionPermanent5XXException: Smtp submission failed. Server 'smtp.hostinger.com' Port '465'. --> Unexpected SMTP server response. Expected: 235, actual: 535, whole response: 535 5.7.8 Error: authentication failed: UGFzc3dvcmQ6
Failure code: cf24
Using New Outlook on Windows for professional communication and productivity
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Has anybody found a resolution for this yet? I've taken the advice in this thread, deleted the Outlook app and reloaded, removed the impacted accounts and re-added. I cannot send outbound email from any Outlook application, but web-based gmail appears to work.
Would appreciate any assistance on this. Thank you!!
Dear all,
If that can help at all, I had the same error and managed to fix it, although it might have occured in a setting different from yours.
I have 3 Gmail accounts, I use one of them to log on to my Microsoft account. I have a M365 Family Edition license.
Because of a security warning I changed my Microsoft account password and bam, since then I could not send messages from the Gmail account linked to the Microsoft account from Outlook on all my devices. The two other accounts were totally fine, which made me think.
Loggin onto my MS account from my PC I saw some information update was needed, certainly because of the password change, which I did. I removed and reinstalled the 'problem' main Gmail account from Outlook on all of my devices and bam, everything worked again.
Hope it works for you as well !
When I revert to classic, I still have this error, so I am assuming when you say install the older version that is something different. How do I install an o, older version?
Thank you!
I'm having the same issue, and -- in addition -- now I cannot add back my Gmail account to the Outlook. Any ideas how to fix it? I tried to uncheck the TLS 1.3 recommended in another question stream [Control Panel], select [network and internet] - [Internet options], in the [Advanced], the following options to check, and uncheck the "use TLS1.3",], but I'm now getting an additional error within Outlook: "We weren't able to set up you Google account with IMAP. You may need changes to your Gmail settings."
It was all working perfectly until yesterday morning (8/8) US time -- i.e. could send emails from Outlook without bouncing back, but now -- after removing the Gmail account and trying to add it back -- Outlook (classic) doesn't let me add the account back. I'm using the Microsoft 365 Family subscription of Outlook.
Any ideas as to how to fix it?
UPDATE: Interestingly -- my other gmail accounts work perfectly in the Outlook, only that one particular gmail account (my main account) is having problems -- i.e. after removing I cannot add it back to Outlook, and I cannot send the emails anymore (it worked intermittently without any changes from my side) from Outlook on my Samsung phone or New Outlook
it only just started and I can not believe what I am reading...I finally startd trusting MSFT again and have to give up now. Super annoying