Have you ever had a crash when rebooting or shutting down your computers ? I believe that many of Windows 8 users have ever had experienced that kind such a trouble. Here are the simple steps to avoid it:
1. Go to new Charms Bar at the top-right corner of desktop screen and click on Search option then type Power in search box.
2. Now you're in search result page. Click on Setting in right-sidebar and then click on "Change what the power buttons do" in the left-sidebar.
3. In Power Option Windows, choose System Settings, scroll down to bottom and you will see "Turn on fast startup (recommended)" option shown in Shuttdown setting session.
Note: In order to open Power Option Windows, you can also type powercfg.cpl in RUN dialog box and press Enter.
4. Uncheck the check box and save setting
Note: If the option is not shown, scroll up and click on "Change settings that are currently unavailable".
5. Restart your system.
Note: if the steps above doesn't fix your problem, you can try these steps:
Open Command Prompt as Administrator by right_click on the bottom-left corner and select the
same option from the Win+X menu:
Good Luck ... !