it will downgrade to 4.1 . i had also updated it 6.0. bt dnt knw how to . cuz shopkeeper did it. nd now its not updating to 5.0.1 plz help.

hello, i have an iphone 3gs. i upgraded it to 6.0 . now i have downgraded it to 4.1 . now wants to update it 5.0.1 but its not updating itunes giving error 3194 and sometimes 1600 . please guide me how to update it.