FixTDSS.exe needed, won't run

Norton Internet Security is telling me to run FixTDSS.exe.  I downloaded it and when I try to run it the system sits and spins for quite a while and finally comes up with "The dependency service or group failed to start."  No further infoermation is offered, and I can't get it to run - I've shut down all apps, don't know what else to try.  I tried downloading it again, same result.  I'm running Windows 7 Ultimate 32 bit.  Any help would be greatly appreciated - my system is in desperate need of assistance!!