Hello Johnsons. I'm Greg, 10 years awarded Windows MVP, here to help you.
There is a bug in Windows Mail right now where certain emails are arriving in HTML code. It appears to be random and doesn't affect the onilne mail provider so you can read the email intact there. I am receiving about one to two of these emails out of a dozen or more a day.
If you want to report this bug to Microsoft you may be able to help improve this product/experience by using the Feedback Hub in Start Menu. While they will probably not see this here in the forums, Microsoft developers DO read feedback from customers that comes in via the Feedback Hub. and this may speed up getting this fixed.
Feel free to ask back any questions. Based on the results you post back I may have other suggestions if necessary.
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