Quote:
Originally Posted by kthor
Thanks for the reply. I've double checked and re-entered a few times both at the Amazon site and the Calibre site. Still no go.
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Re-entered what at the Amazon site and Calibre site? Those sites should have nothing to do with your email credentials.
Did you follow the instructions at the link provided in the error message?
https://support.google.com/mail/answer/14257
You need to tell GMail that the automated process attempting to access your account really is you. Once you follow the steps in that link, Calibre should be be able to send through the gmail account without issue.
I've run into this before with website auto-mailers.