I don't know why the menu isn't there sometimes. Its a pain. Since repair won't repair PC, he might have to do a reset or a fresh install. Both choices require him to reinstall all his programs again.
is there anything on C drive he wants to rescue? try making this on another PC: http://www.howtogeek.com/howto/windows-vista/use-ubuntu-live-cd-to-backup-files-from-your-dead-windows-computer/
once he has copied everything off laptop he wants to rescue, either do a reset or fresh install
boot from installer, on 2nd screen after languages, choose repair this pc, not install
choose reset this PC
keep files and settings - files only include contents of library folders so documents, music, videos, pictures. Settings are logins,
Wipe everything - this resets Win 10 to new and removes all his files
Either chocie, PC will restart and reinstall win 10.
boot from installer
follow this guide: http://www.tenforums.com/tutorials/1950-windows-10-clean-install.html
when you reach the screen asking for licence, click "I don't have a key" and win 10 will continue to install and reactivate once finished
On the screen where you choose where to install win 10, if it gives you an error about GPT drives, delete all the partitions on the hdd and press next. If it still gives error, cancel out of the installer and restart PC and start installer again, it will accept next on that screen this time (some PC just need a restart here)