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An error occurred while sending mail. The mail server responded: 5.7.1 The message contains an unauthorized custom from address because the 5.7.1 associated ac

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  • 4 have this problem
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  • Last reply by Zenos

kernparker
kernparker
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I started getting the above error message this morning. I had made no changes to anything and had successfully sent Thunderbird messages before the error started to occur. I'm a gmail user and I use Thunderbird in imap mode. I have installed the latest Thunderbird update and I've restarted, both to no avail.

I started getting the above error message this morning. I had made no changes to anything and had successfully sent Thunderbird messages before the error started to occur. I'm a gmail user and I use Thunderbird in imap mode. I have installed the latest Thunderbird update and I've restarted, both to no avail.

All Replies (1)

Zenos
Zenos
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Who is your provider? There are several posts to this forum describing the same error message and the same error number. I wonder if you're all using the same email provider and they have a system fault at their end.

https://support.mozilla.org/en-US/questions/1014327 https://support.mozilla.org/en-US/questions/1014334 https://support.mozilla.org/en-US/questions/1014299

Modified by Zenos