Disabling fast startup makes Windows perform a full shutdown instead of a hybrid one. Boot time becomes a little longer, but shutdowns are cleaner. This often fixes problems such as updates not applying, dual-boot systems not seeing other drives, devices not resetting properly, or a PC that will not sleep or wake correctly. No files or settings are lost. Fast startup is a Windows feature; Mac does not have it.
Why this happens
With fast startup on, Windows does not fully shut down. It closes your session but saves the system kernel to a file, so the next boot loads that file instead of starting fresh. This is a mix of shutdown and hibernation.
Because the system is not fully reset, some hardware, drivers, and updates do not initialise cleanly. Turning fast startup off forces a true shutdown each time, which clears those issues.
Is this normal?
Yes. Disabling fast startup is a common and supported fix, especially on desktops, dual-boot machines, and PCs with driver or wake problems.
Does it cause any problems?
The main effect is a slightly slower boot, most noticeable on machines with a hard drive rather than an SSD. There is no data loss and no harm to the hardware.
How to fix or check it
- Open Control Panel, then Power Options.
- Click Choose what the power buttons do on the left.
- Click Change settings that are currently unavailable.
- Untick Turn on fast startup, then Save changes.
- Restart to confirm the change takes effect. If the option is missing, enable hibernation first by running powercfg /hibernate on in an admin Command Prompt.
Frequently asked questions
Will disabling fast startup slow down my PC?
Only the boot takes slightly longer. Day-to-day performance is unchanged, and on an SSD the difference is usually small.
Does fast startup exist on Mac?
No. This is a Windows feature. Macs manage sleep and startup differently and have no equivalent toggle.
Why do updates only install after I disable fast startup?
Some updates need a full shutdown to finish. Fast startup skips that, so a true restart or disabling the feature lets them apply.