Long time ago, I was trying to sign up an e-mail account for my friend, Nattaporn, at live.com. But I was unable to. Live.com tell me that the user name "nattaporn" contains word that is not allowed.
Today, I tried to sign up with my mother name again and got the same error message.
What the two names have in common is the "porn" segment which is very common for Thai names. I am sure there are millions of Thai people those have their names containing "porn" (-พร). For instance, Siriporn (สิริพร), Nattaporn (ณัฎฐ์พร), Tuangporn (ตวงพร), Pornchai (พรชัย), Pornsook (พรสุข). "Porn" is, in fact, a good word in Thai which means "Blessing".
Live.com may has to reconsider this name filtering criteria since it is losing many of Thai users.