Ps3 network under mantenance

Hello,

i have tryed to do a internet check on my ps3 for 2 days and it is beginning to give me the hump lol. every time i do it it connects to the modem obtains the ip address and that but as soon as it gets to playstation network it says failed 'sony entertainment network is currently under going maintenance' but i have one of my mates profile on my ps3 as well but as soon as i sign in on that on it works so how come it wont work for mine but works for my mates help me please !!!!!!