It means that the owner of the profile has chosen to hide his or her profile. You cannot enter the profile, and you cannot send messages to this member at this time.
It can be many reasons for that. It's up to each member if they want to use this feature.
No, sorry... we cannot. We have to respect this members wish to not receive messages at this time. Please try again later. Maybe this member soon will set the profile back to "visible" again.