A virus entered in my computer, I had to uninstll avast to install it again, I couldn't and I had to restore the system with this tool of windows. Sddely I see that avast is ghost in my computer, is there but isn't there, every option is an error, like if I had only the program but no more files, I cannot delete it anyway, windows uninstaller, add programs, other uninstallers, the self avast tool, noway, I have to install it again, but I canot anyway, plase help.