“…domain name contains a protected word or inappropriate language…”

I have been attempting to use domain.live.com to register www.profiresites.com for email services. Like many other users, I am experiencing difficulty successfully registering because of this error.

The purpose of www.profiresites.com is to allow fire departments across the country to create their own sites. I do not understand where the "protected word or inappropriate language" comes from. There has to be an easier way for a resolution to this problem than posting it online as a new post every time someone has this issue. No number to call or chat was offered.