How do you report a product bug to Microsoft?

Neither Outlook, nor Microsoft don't have to do anything with your problem. There are only two persons who can address it: one is network administrator of knology.net, by adjusting their method of determining what content is considered spam; another is yourself, by adjusting your content so it does not resemble spam.  If you post the text of your email, may be we will be able to guess (but only to guess; only recipient network admin can tell for sure, by looking into the log) which part of it is most likely to trigger spam detection.

Help

Any Emails sent to "knology.net"email domain using my Comcast.net email address, utilizing Microsoft 2016, get rejected from their service because the message contains SPAM content.  This is consistent with addressee with that domain.  In the past I worked with Microsoft Assurance level 3 support to no avail, and worked with Comcast support without solving the issue.  If I log into the mail account on the Xfinity/Comcast server, and send the same message, it is not rejected.  The problem is with Microsoft 2016.  It is really aggravating.  I will be glad to send anyone examples of the issue.  I would like to report it directly to the Microsoft Office Outlook 2016 folks.

Help

If what you reported is actually a bug, or at least the feature is not sufficiently documented, you won't be charged. I have reported dozens, and paid $0.00. But if you waste their time on something that you should have found yourself, then yes, their time costs money.

Only if you are willing to pay for the privilege of reporting the bug! Bah! Humbug!