How do I remove this virus called svchosts.exe and yes it has a "s" after host?

My little sister downloaded this program and i got in time to stop her from completing the installment and deleted the file. When my security pops up and it ask if I should allow it to access the Internet for sure I didn't allow it and my firewall also asked if I should allow so I didn't allow too. I want to delete it but it doesn't show up on my computer. My firewall says it is located on C:/windows/ but it's not there I even allowed hidden files to be viewed and it's still not showing up, it's like invisible or something.