Trojan syswo64/Powliks!gm

Late last week cleaning files I saw that I had a huge number of windows and internet files having run ...( 20,000 ...usual was less than 100 ) so ran scans and saw the trojan and norton 360 said ok after restart ...this is happening every time and norton pops up and says that the trojan has been blocked agian and i have to restart ...but it is still running huge numbers of file on my pc even after norton says it has been blocked . Norton does not seem to understand what it is or how to fiux it ???? It does not end after the restart but just comes back each restart...What can I do ???