Hi @RalphReichts ,
Thanks for visiting our forum, then here we mainly focus on general issues about Exchange server. According to your description above, you cannot login the Amazon Fire Email App with your hotmail account.
It seems that your issue should be more related to hotmail or Amazon right? If this is the case, it is suggested to post a new thread to the dedicated Answers community for Hotmail or Amazon in order for you to get better response:
Hotmail Forum & Amazon.com Help: Set up Email on Your Fire Tablet
Thanks for your understanding and hope your question will be resolved soon.
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