Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello FRANCISCO
I'm Diane, an M365 Apps & Services MVP specializing in Outlook and I’m happy to help you today.
Does it only happen with mail sent to that domain or to all mail you try to send?
Which version and build of Outlook are you using? See File, Office Account for the information.
Try this - in File > Options > Mail - in the Message Format section near the bottom, change the Automatically wrap text at character to 65 and see if it helps.
-- Diane
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