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
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)
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
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