Defrag won’t run in Safe Mode – Several users reported that they can’t defrag their drive in Safe Mode. This usually happens if your installation is corrupted. If SFC or DISM scan can fix this problem, you might have to reinstall Windows 10.

Does Windows 10 automatically defrag?

Windows automatically defragments mechanical drives, and defragmentation isn’t necessary with solid-state drives. Still, it doesn’t hurt to keep your drives operating in the most efficient way possible.

How do I do a disk cleanup in safe mode?

Windows 2000, XP, Vista ONLY when connecting to Internet via DSL or cable modem choose Safe Mode with Networking. 4) Click START > PROGRAMS > ACCESSORIES > SYSTEM TOOLS > DISK CLEANUP. 5) Make sure you check boxes to remove all temporary, deleted, and other files not in use by your system. 6) Click OK.