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Authentication failure: unknown user name or bad password. [Error="ProxyNotAuthenticated" AuthResult=0 Proxy=HE1PR0201MB1788.eurprd02.prod.outlook.com:1995:SSL]

  • 4 replies
  • 73 have this problem
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  • Last reply by kmjh

As I open Thunderbird one of my account asks me the password. Once I fill the box, the error message above appears ( Non riuscito l'invio della password per l'utente ******@outlook.com. Il server di posta pop-mail.outlook.com ha risposto: Authentication failure: unknown user name or bad password. [Error="ProxyNotAuthenticated" AuthResult=0 Proxy=HE1PR0201MB1788.eurprd02.prod.outlook.com:1995:SSL] ) I'm sure the password it's correct.

I think this error started appearing after the new update.

Thanks to everyone for the support, and sory for my bad english ;)

As I open Thunderbird one of my account asks me the password. Once I fill the box, the error message above appears ( Non riuscito l'invio della password per l'utente ******@outlook.com. Il server di posta pop-mail.outlook.com ha risposto: Authentication failure: unknown user name or bad password. [Error="ProxyNotAuthenticated" AuthResult=0 Proxy=HE1PR0201MB1788.eurprd02.prod.outlook.com:1995:SSL] ) I'm sure the password it's correct. I think this error started appearing after the new update. Thanks to everyone for the support, and sory for my bad english ;)

Chosen solution

I had the same. I rechecked the settings shown on the Outlook server settings help page.

I asked myself if Thunderbird might find other settings so I deleted the account and set it up again. It failed again on POP so I tried IMAP, which worked.

I don't know if this is intentional. None of the help pages I have looked at up to now has said anything about POP being suspended or discontinued.

However, following some links to POP server settings, I found some advice to set a checkbox for POP. And when I found it, it was set to "off". I haven't checked the outcome of seeing this to "on" but it seems logical that if it's set to "off" then Thunderbird won't be able to connect using POP.

I don't recall any warning from MS that this would be switched off automatically.

https://outlook.live.com/owa/?path=/options/popandimap

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Chosen Solution

I had the same. I rechecked the settings shown on the Outlook server settings help page.

I asked myself if Thunderbird might find other settings so I deleted the account and set it up again. It failed again on POP so I tried IMAP, which worked.

I don't know if this is intentional. None of the help pages I have looked at up to now has said anything about POP being suspended or discontinued.

However, following some links to POP server settings, I found some advice to set a checkbox for POP. And when I found it, it was set to "off". I haven't checked the outcome of seeing this to "on" but it seems logical that if it's set to "off" then Thunderbird won't be able to connect using POP.

I don't recall any warning from MS that this would be switched off automatically.

https://outlook.live.com/owa/?path=/options/popandimap

Thank you very much!

Thank you, Zenos.

Looks like in Microsoft are making changes to interfaces and accounts and they may have switched off POP, or whatever.

Thanks again.