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Logon failure: unknown user name or bad password

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  • Last reply by S3an

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I've been using Thunderbird without issue for business for nearly eight years now. I currently run it on a lap top with Windows 7 Pro. There is only one account/e-mail address on Thunderbird.

This morning when I went to check my e-mail I was prompted for my password then received the error "Sending of password did not succeed. Mail server exchange.company.com responded: Logon failure: unknown user name or bad password." I retried the password, restarted Thunderbird and tried it again but still received the same error. I sent a test e-mail from Thunderbird which went through just fine. I'm also able to log on to the exchange server via web browser and I am able to send and receive e-mail on my mobile device.

I've cleared all of the saved passwords from Thunderbird and I've verified the account settings but I'm still unable to download any e-mail to Thunderbird.

Apart from deleting the account, I'm not really sure what to do here. Any help would be much appreciated!! Thanks.

I've been using Thunderbird without issue for business for nearly eight years now. I currently run it on a lap top with Windows 7 Pro. There is only one account/e-mail address on Thunderbird. This morning when I went to check my e-mail I was prompted for my password then received the error "Sending of password did not succeed. Mail server exchange.company.com responded: Logon failure: unknown user name or bad password." I retried the password, restarted Thunderbird and tried it again but still received the same error. I sent a test e-mail from Thunderbird which went through just fine. I'm also able to log on to the exchange server via web browser and I am able to send and receive e-mail on my mobile device. I've cleared all of the saved passwords from Thunderbird and I've verified the account settings but I'm still unable to download any e-mail to Thunderbird. Apart from deleting the account, I'm not really sure what to do here. Any help would be much appreciated!! Thanks.

Chosen solution

The problem was solved. Apparently the POP stack had to be reset from the Exchange side.

Hopefully this helps someone in the future...

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I just noticed that I get an error message that reads "Sending of username did not succeed." as well. So it's bot the username and password.

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Chosen Solution

The problem was solved. Apparently the POP stack had to be reset from the Exchange side.

Hopefully this helps someone in the future...