All of a sudden, after working correctly for ages, I am unable to restart from Windows to Mac OS via Bootcamp. The startup disk control panel shows both systems, Mac and Windows, but selecting the Mac disk just restarts in Windows. I can get back into Mac by restarting with the Option key pushed down, but - and this is the scary bit - if I shut down, restarting puts me straight back into Windows.
iMac 27″, macOS 10.13
Can you set the default os to macOS from the macOS side, and reboot and test? The Mac should boot macOS.
Your default OS seems to be Windows. See Start up your Mac in Windows or macOS with Boot Camp - Apple Support for reference.
Yes, Boot Camp appears to have arbitrarily decided that default OS is Windows. My problem is precisely that having followed the instructions supplied in the link, it still defaults to Windows.
Thanks, that resolved the problem.
Excellent!
Restart in Mac OS from Windows not working
