Unable to download apps on marketplace in nokia lumia 800 on wndows 7.8

                                                                                                                                                                                                                               HI,                                                                                                                                                                                                                                                                                                                                                                                                                                            I have nokia lumia 800 windows phone 7.8 software,I feel inconvenience with this windows phone because am unable to download applications from marketplace while am trying it displays that the windows live ID service is unavailable at the moment.try again later.After this am unable to update any applications&any accounts in my windows phone.                                                                                     And i have reset the phone many times previous with creating new windows live ID accounts because it does not opening the previous account.So, i have problem with this also while am opening new it displays You have reached the maximum number of accounts allowed for a windows phone.Contact a support person or your service provider to help you.Or if i still try it again it displays that We are having a problem that we cannot solve at the moment.Try again later.                                                                      By with this reasons am unable to dowload any applications from market place,So please help me in this problem.                                         THANK YOU,