This is an excellent question, thank you. I thoroughly enjoyed it because I found it to be pretty difficult to answer correctly. I suspect that "most characters illegal" means all except the tab (char(9)), linefeed (char(10), 0xA), carriage return (char(13), 0xD) and the space(char(32) 0x20). I am curious to find out how the results of your

select * from #t for xml auto;

will look in SSMS results window, will definitely do it tomorrow morning.

Oleg