[This name does not exist]

when I try to look at a friends profile it says "This name does not exist" why does it do that and why cant I see the profile?

[unavailable names when looking at adult profiles]

I have bought lindens, I am way over 18 and my preferences are set to G,M,A and I still cant go to adult areas or see adult profiles...I am also new only been in SL for 6 days....is there a certain amount of days I have to be in the game before I can access adult content even though I am old enough?