This is a difficult one,If its what I think it is then
there is alot of hidden files involved which change their
name when you delete them.You probably never really
delete it if your in normal mode but it just changes the
name of the files, Real Time protection isnt designed for
Trojans although it does block a few, now you have it on
your system the real time protection cannot help you.
The genuine Kavsvc relates to Kaspersky Antivirus but its
clear we are not talking about that, It's more likely to
be the Narrator infection.Also because this uses random
names that change it also makes finding the solution
harder because each system has different file names
involved.
You need expert advise on this and using 'Hijack this'
will show most of the bad files and then you can use
other tools to show the hidden files then remove them all
at the same time,The fixes will still need to be run in
safe mode so your best starting with Ewido,MSAS and
Ccleaner then move onto Hijack This if it doesnt remove
it for you,
You can then post your Hijack log over at
SpywareInfo/Greyknight17 or TomCoyoyte and receive help
in removing this.
Also Kevin (Greyknight17) has abit of info on Narrator
but do not follow the advise unless you feel confident as
it involves random files so you really need assistance on
this from experts in a forum enviroment but the guide is
good to let you see whats involved
http://www.greyknight17.com/spy/Tutorials/KavSvc.htm
If you need help with anything just let me know and I
will assist if I can
Regards
Andy