Are you still having issues with your drive? Generally, the things to consider are cleaning your files (ccleaner, disk cleaning), thoroughly uninstalling unwanted programs (iobit uninstaller), looking for threats (spyware doctor, avast). You may also check your task manager to see if your system is on high cpu usage even if it doesn't seem to do a thing, which means you have a process doing probably nasty stuff (a virus).
Yes, The issue is still exist. I've used ccleaner several times. seems that my problem is something else. and yes, I've scan my computer with ant-virus too. there isn't any virus.
Let's assume you ran ccleaner (data/app cleaning and registery cleaning), have you ran disk cleanup? Right click on you hard drive, select properties, then select disk cleanup, once it has ended finding what to clean, click on clean up system files (it will re-run) then examine carefully what it suggests to clean up, generally I clean everything, but if you have a previous installation of windows or if you put you machine on long sleep often you might wanna keep some stuff ... You can also remove restore points. Anyway when you do that you might try to share a screenshot of the result of disk cleanup so that we can guide you through it.
A long/well-established virus won't be detected by an antivirus (no matter how good it is), antiviruses seem to be good at stopping new viruses but seem to be bad at detecting powerfull running ones ... So start task manager when your machine isn't doing anything (close your internet browser), wait for a little time and examine CPU Usage (at the bottom of the window, in the middle) it must be somewhere between 3 (maybe less) and 8 %, if not then you should try to see what's running and using your cpu ....
If you haven't done it, I also advise you to install spybot search&destroy (a free antispyware that works very fine) and look for rootkits. Also install IObit Uninstaller (a free uninstaller program) and examine what is installed on your computer and remove stuff that you really don't know.
You could also use some software to examine the occupied space on your disk (Unfortunately I don't know any for windows).
If only I had your machine under my hands ^^ Anyway don't hesitate to post screenshots.