"The username violates our guidelines"

Unless I misinterpreted it, the message implies the supposed violation is with my user name, not anything I wrote but I admit that does not make sense either. I suspect the problem is caused by some buggy algo. In regard to big corporations, I must give kudos to Amazon. I had a similar experience where without explanation I was blocked from posting reviews on Amazon for certain products I had purchased from them. The block made no sense to me because most of my reviews were very positive and only a few negative and in my opinion even the negative ones weren't that negative. Unlike Microsoft however, I was pleasantly surprised to find that I could call Amazon's customer service and when I did the phone was answered by an actual human being who listened and was able to lift the block while I was on the phone. Does anyone know if there is such a number for MSFT?

I fixed my issue by installing the Microsoft Start News App on my Android phone (Microsoft Start: News & more - Apps on Google Play).

I started the process using the Microsoft Start home page (first appears when you open MS Edge) on the MS Edge browser on Mac (Big Sur). When I was configuring MS Start, it is then I ran up against the "...username violates out guidelines," issue when signing up for the Community section. The username line in the 'sign up' dialog was EMPTY. I went through the normal motions and changed my Full Name under the "Your Info" section of my MS account, but nothing worked. No matter what I did, while using MS Start home page (or website) in the browser on my Mac, the username was always empty when trying to sign up for the Community section. I believe the empty username is a data fetch error. Furthermore, since the username line is empty in the Community sign up dialog box, it violates user guidelines of having a blank username. So, it is not a conspiracy but a programming issue (or maybe a browser specific issue not caught in testing).

I stumbled on a post that talked about the MS Start App, so I decided to try that on my Android phone. Once I installed the app outlined above and logged into it, I could see my preferences were indeed sync’d (news types, notifications, etc.) from when I set them on the MS Start home page on my Mac. However, I noticed that after I logged into the app there was still an error showing. The error had a Contact Support link and it started workflow for an MS Rewards support ticket. So, I did 2 things and, of course, I’m not sure if both or one of these things fixed it. 1). under the sign in portion of the MS Start app on Android, there are a few options. One option is 'My Rewards.' I touched 'My Rewards' and essentially joined the Rewards program (it looks harmless and didn't cost anything). Once I did that, the error message that was appearing on the sign in portion of the app on Android went away and a 'dashboard' showing my points was displayed in its place. 2). I then went back to the home page of the app (still on Android) and picked a news article. I then went to comment on it. When I did that, I got the same Community 'sign up' screen I saw on the MS Start home page using my Mac but this time, the username was populated (with my Full Name in my MS Account). So, I touched "Join" and that was it; it worked. So, I was able to join the Community and comment on a news article all in the app on Android.

So, I went back to MS Edge on my Mac, picked a news article and tried to comment. It asked me to sign (I assume to try to perform the Community requirements needed to comment). After signing in, I was able to comment.

To me, it seems the web app (browser) is not properly pulling the Full Name from the "Your Info" section of the MS Account, but the android app is. It may be possible to use Edge on Windows, or some other browser and the bug may not appear.

I will say the app on Android is a bit buggy (screen flashes) and the website is still kind of clunky (obviously). I hope these things will be fixed as they refine the platform and the multiple ways to access it.

It's still broken. 10 FEB 2022, What's it been? Almost 2 months now?

I'm editing this because I found a fix for it. It's just a matter of creating or updating the username, logging out of MSN, going back to article discussion, Where it says Join the Discussion Log In .... click that and do so. Then my username update appeared and it was all good. I might have refreshed a page or two in that process...

Do you actually see a username when you're on this page? Is it the same error?

I think what I see is actually just a bug. I think that my account is really old and the call the service is making to get my "username" is not actually returning my username. So it sees a blank, which of course would not be a valid username. It says, "This is the name from your Microsoft account." And yet no name is ever shown.

This form of blocking has been going on for years, not months. I never did find out any information about it. Microsoft loves to obscure stuff. They can't store passwords correctly, either.