I use internet data card of BSNL to my laptop and i install KasperskyIS 2010 but suddenly my laptop cannot?

connected to the net, lastly it was defected with autoru.inf- trojan program: trojan.win32AutoRun.acq,i am not able to delete this from my flash drive nor from my harddisk. This is not the question I want but the main problem for me but the main is it cannot connect the net where as in other laptop it is able. I don't want to format my laptop. Is there any means to solve it to connect the net with internet data card wihout formatting. I don't want to format it. I use win vista.