When your screen freezes, one of two things might have happened; the app that’s currently in the foreground has frozen your display, or your system is frozen. If it’s the app that’s causing the problem, you don’t need to shut down your system. You can fix a frozen display by refreshing it.
Fix Frozen Display
You can fix a frozen display via the built-in refresh tool on Windows 10.
On your laptop or desktop press Win + Ctrl + Shift + B. On a tablet, press the volume up and down button at the same time, in quick succession, three times.
Your screen will flash and the stuck/frozen app should either quit or crash, or maybe it will fix itself. This is the simplest way to fix a frozen display. If your screen does flash but the app still won’t work nor let you switch to other apps or your desktop, you can try quitting it with Task Manager.
In the event that task manager refuses to open, your only choice is to force shut down your system by holding down the power button.
If you’ve recently updated to the Windows 10 April Update, you might be encountering a bug whereby Chrome and Cortana, and some others app freeze. This is a known bug that the above solution fixes temporarily. Microsoft has released a proper fix for it via an update, update KB4103721.
You should be able to install KB4103721 from the Settings app. Open the app, go to Update & security, and select the Windows Update tab. Check for new updates and this one ought to appear in the list of available updates. Let Windows 10 download and install it. Restart your system if needed.
If the update isn’t detected, you can wait a day to see if it appears or you can download the update directly from Microsoft’s official catalog website. Simply download the update and make sure you download the correct one i.e. 32-bit or 64-bit for your system. The file downloads as an MSU file that you can double-click to run, and install on your system. If a restart is required, the update will likely say as much however, if it doesn’t and installing the update doesn’t fix the problem, restart your system anyway.
This update only fixes the Chrome freezing problem. If your system is freezing, or you’ve had this problem since before updating to Windows 10 1803, the cause is probably something else and the update will not fix it.