If you have files that are difficult to remove, then you use safemode or boot scan
" Avast Antivirus offers a "boot time" virus scan of your PC. This allows the antivirus engine to scan all of the files on your hard drive before any other programs load - useful in cases where you have an infection which cannot be cleaned because the "file is in use"
In malwarebytes you also have an extra tool " FileASSASSIN "