This one surprises many people. When you click "Shut down" in Windows 8, 10 and 11, it does not fully shut down. It uses a feature called "Fast Startup".

What Is Fast Startup?

Fast Startup is a feature that saves part of the Windows kernel to disk when shutting down. This means that on the next boot:
  • Windows loads from that saved state
  • Boot time is faster
This is a partial hibernation. And probably reminds most of the "Sleep" feature on laptops, which also saves the state to disk. Or the "Hibernate" feature, we had on Windows XP.

Why Can This Cause Problems?

Because drivers and hardware may not fully reset. Common issues:
  • Network adapter behaving strangely
  • USB devices not detected
  • System hangs after updates
  • Audio devices not working
  • Graphics issues after shutdown
Funnily, these issues often go away after a Restart, which does a full shutdown and bypasses Fast Startup. I have countless times experienced users swearing they shut down their PC every day. However, when I check the system uptime, it shows they have been up for days. This is because they were actually using Fast Startup, and never did a true shutdown.

How to Check System Uptime

  • Open Task Manager (Ctrl + Shift + Esc)
  • Go to the Performance tab
  • Click on CPU
  • Look at the "Up time" value
If it shows several days, then you have not done a true shutdown in that time.

How to Disable Fast Startup

  • Click Windows Button, start writing Control Panel and open Control Panel
  • Search, top right, write Power Options
  • Click on Choose what the power buttons do
  • Click on Change settings that are currently unavailable
  • Uncheck Turn on fast startup under Shutdown settings
  • Save changes

Why Disable Fast Startup?

Disabling Fast Startup can help resolve hardware issues, ensure a full shutdown, and prevent problems with dual boot setups. It was meant for speeding up boot times, but it can cause more headaches than it's worth for many users. With todays hardware, the boot time difference is often negligible, and the potential issues outweigh the benefits.

What You Should Not Do

  • Do not rely on Shutdown for troubleshooting - use Restart instead.
  • Do not assume booting fresh fixes driver issues if Fast Startup is enabled.
  • Do not disable hibernation if you actively use laptop sleep features without understanding the difference.

What You Can Take Away

  • Shutdown is not always a true shutdown in Windows 8, 10, 11.
  • Restart is more reliable for fixing issues. - Literally, have you tried turning it off and on?
  • Disabling Fast Startup can solve mysterious hardware problems.

Final Thoughts

Understanding how Fast Startup works can help you troubleshoot and maintain your Windows PC more effectively. If you experience hardware issues after shutdown, consider disabling Fast Startup for a more consistent experience.