Update error 3F4B-40A3-1600-0702-C000-0099 - but it isn't banned or been modded!! x

Hi, My sister gave me an old Xbox 360 for my girls but when I have tried to download by Xbox Live profile it comes with an update....I proceed with this update until it throws the above error code up. This site states that it is because it has been modded,
but it hasn't. I have also visited the Xbox Live policy and enforcement website, checked the console and it says it is not banned.......my account is also perfect......can someone please help? I have also tried to do a manual update via USB but the same
error comes up again.........my connection is fine as my existing Xbox is connected and working online. Hope someone can help.

Thanks

Jo xxx

:)

 

xbox won't update

Modem Brand and Model Number: sticker is gone

Router Brand and Model Number: sticker is gone

Wired or Wireless connection: None

Update Error Message: 397F 3F4B 1600 0702 C000 0099

Update Error Code (6 sets of 4 digits/letters each): 397F 3F4B 1600 0702 C000 0099

What you've tried: http://forums.xbox.com/xbox_forums/xbox_support/f/7/t/166045.aspxhope ya can help me

 

Need Help banned console cant install the new update

my error code is

3F4B-4099-1380-0702-c000-0099