I'll say it again, the error means EXACTLY what it says "illegal XML character." It does NOT mean that the message got truncated. It does NOT mean that it...

Thanks, everyone, for the feedback.

Regarding the questions/issues:

Working on this. I will post a self-contained, runnable...

Thanks for this article. This has never happened to me, but I appreciate your explanation of what to do if it does.
-webrunner

Thanks for this great introductory article! I look forward to the rest of the Stairway.

Note, I learned this about the beginning question mark for XML documents:

Thanks, nice question.

Btw this returns 11 (or rather, '11'):
DECLARE @s VARCHAR(10) = '1'
SELECT @s += '1'
SELECT @s

- webrunner

Thanks for the question, I learned something about this wacky function.

- webrunner

Thanks, very helpful question!
- webrunner

Thanks for this heads-up. I've seen the tail-log option appear for me as described in the article. Luckily I did check the different dialog boxes and noticed it, so I...

Thanks for this instructive question!

- webrunner

Thanks, this question taught me something today!

- webrunner