|use winrar to se all hiden files of your pen drive|
start - run - cmd
change your directory to the letter of your pen driver , it is D or E ecc.
attrib -r -h -s atuorun.inf
and next type:
when it asks would you like to force a dismount , pres Y.
then it asks about naming your pen drive
then it formates it .
be carefull first take care of your data first , those you say are hidden. remove them first . then try to disband autorun.inf
it worked for me .!!