Q: update 4.3.3 dilema

hello ,  I have just scored an ipad 2 wifi which sadly is on IOS 4.3.3 ,which now I have it want to update it to the latest and greatest of course so I can run the apps we have on our other devices ...  and any attempt to update via itunes (multiple machines , different cables , no antivirus , you get the point) does not work at all coming back with the wonderful "error 9" . Now I have scoured the internet and seems there is quite a large number of people with the same issue , has anybody resolved it or had any response from apple as to why it does not work ??? the model runs the latest 9.1 as my other 2 iPad work fine ..

Please help