If need be, you could download those files from another computer, to use on yours.
Well, just to help make sure that your system is clean, you might consider using the tutorial below to create a bootable Windows Defender Oflling DVD/USB to use to scan your system with at boot. If need be, you can create it on another 64-bit computer to use on yours.
Windows Defender Offline
Once you are sure your system is clean, then you could also do a
system restore at boot using a restore point (if available) dated before this happened to hopefully undo and fix it.