Open your registry and find the key below. 

Change the value of 'AutoReboot' to equal '1' for automatic reboot, or '0' for disabled. 

Restart Windows for the change to take effect. 

Note: This function can also be enabled from 'Control Panel | System | Startup/Shutdown | Automatically Reboot'. This feature is enabled by default on NT server, and disabled on NT Workstation. 

Key:[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CrashControl]
Value Name: AutoReboot
Data Type: REG_DWORD
Data:(0 = disabled, 1 = enabled)

Back to Windows Tweaks