the last thing i remembered added in the context menu was a bat file in "send to" folder(not without my consent so not malware issue).
The bat file's function was to move files in a folder within the folder it was originally on.
ex.
D:/Folder/filename.jpg
I right click on it>send to>new folder.bat
new location
D:/Folder/filename/filename.jpg
but I found it useless so i went to 'send to' folder to delete it.
And now Right click stopped working!
I disabled all(except avast,winrar,and spybot) non windows context using shellextview.
But it still doesn't work!
I know it's not malware(that's why I posted it here instead of the HJT section).
could be in the registry.