CNG Service Defaults in Windows 7
Kernel Cryptography, Next Generation by Microsoft Corporation.
Default Settings
| Startup type: | Boot |
| Display name: | CNG |
| Service name: | CNG |
| Service type: | kernel |
| Error control: | critical |
| Group: | Base |
| Path: | %SystemRoot%\System32\Drivers\cng.sys |
| Registry key: | HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CNG |
Default Behavior
CNG is a kernel device driver. In Windows 7 it is being loaded by Boot Loader before Kernel initialization. If CNG fails to load, Windows 7 attempts to write the error data into Event Log and restart the computer, using the Last Known Good configuration. If the Last Known Good configuration is not valid, Windows 7 startup ends with a Stop error. If you remove or disable the CNG service, Windows 7 won't start.
Restore Default Startup Configuration of CNG
1. Run the Command Prompt as an administrator.
2. Copy the commands below, paste them into the command window and press ENTER:
sc config CNG start= boot
sc start CNG
3. Close the command window and restart the computer.
The CNG service is using the cng.sys file that is located in the C:\Windows\System32\Drivers directory. If the file is removed or corrupted, read this article to restore its original version from Windows 7 installation media.