If SFC could not fix something, then run the command again to see if it may be able to the next time. Sometimes it may take running the sfc /scannow
command up to 3 times with Fast Startup
turned off and restarting the computer
after each time to completely fix everything that it's able to.
If not, then run the Dism /Online /Cleanup-Image /RestoreHealth
command to repair any component store corruption, restart the PC afterwards, and try the sfc /scannow
If still not, then do a system restore
using a restore point dated before the bad system file occurred to fix it. You may need to repeat doing a system restore until you find a older restore point that may work.