iPhone 4 GSM trouble updating

i have a iphone 4 on ios 5.0 never ever been jailbroken ever. im trying to update to ios 5.1.1 with an ipsw file obtained from:

http://appldnld.apple.com/iOS5.1.1/041-4293.20120427.3DRyb/iPhone3,1_5.1.1_9B206 _Restore.ipsw

so its authentic.. from an apple server and all...

now when i try to update or restore using shift+restore/update button whenever it gets to verification it throws error 3194

ive been reading all over the web for help ive tryed messing with hosts files which ive found is useless for me as ive never jailbroken,

ive tryed on around 5 different PCs using latest itunes on all of them , 3 windows 7, 1 was vista , 1 was xp,

ive tryed disableing firewalls and virus programs , ive tryed adding ports,

the list goes on......

now your going to say why not update to ios 6 directly through itunes , i do not want to as ive had a few friends have problems with alot of games not working and some other reasons, but i would really like to update to 5.1.1 for now till 6 has been around for a while, any new suggestions would be awesome, i dont no anyone with a mac but if i find someone with one ill try it on there computer also, thanks jamie.