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Author Topic: Proper MIME prevents DKIM failures in Outlook  (Read 14494 times)


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Proper MIME prevents DKIM failures in Outlook
« on: November 27, 2018, 10:36:08 AM »

At Postmastery, we work for various ESPs and brands to optimise email delivery. Recently, one of our clients faced a mysterious DKIM failure when sending mail to Outlook.com domains.
Please find below the full case description.

Our main finding: Use proper encoding and always test your output at a header level with various large ISPs like Outlook, Gmail and Yahoo. We advise using Quoted-Printable transfer encoding for best results.


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Re: Proper MIME prevents DKIM failures in Outlook
« Reply #1 on: November 27, 2018, 10:48:10 AM »

Thanks so much for posting this and sharing it with our Forum.  This is valuable information for all of our PowerMTA customers.