I need help with my computers speed I know the problem but not how to solve it?

well as the question says I have problems with my computers speed. about a month ago I installed something to my computer I cant remember what it was but since then a message started coming up saying windows cannot find C:\WINDOWS\KesenjanganSosial.exe

and since then my computers speed was reduced and kept crashing i fixed the crashing problem but not the speed. and recently another message has been coming up saying

windows cannot find

C:\WINDOWS\17PHolmes1554.exe

sorry for the long question but does anyone know how to fix these ive tried system restore and I don't want to reinstall another OS is there any other way?

I need help with my computers speed I know the problem but not how to solve it?nortan antivirus

Using a registry cleaner can clean up your computer and then make your computer faster,Why?the reason is that there may be some regsitry errors and remnant,corrupt files and temp files in your computer to cause "computer slow".

Everytime you install and uninstall software on your computer and surfing online you create junk in the computer registry.over time, the registry can grow to enormous proportions, especially if the various programs you've installed do not do a good job of deleting and/or updating it's Registry entries.You need to scan and clean your computer with registry cleaner to make it fast.Good Regisry Cleaner will improve your computer and Internet performance dramatically!