While working in the group policy editor I entered a program and accidentally pressed OK. The system now does not allow me to enter the group policy editor again and I cannot use any program... Kindly help.

There is no other administrator account enabled except the one I use.

Boot into Safe Mode so that you can use the built-in system Administrator account and change the settings.  To boot into safe mode:

1. Press
WinKey+I to display Settings.

2. Click the Power Options icon.

3. Hold down the
Shift Key while you click the Restart option.

4. On the first screen, select
Troubleshoot.

5. On the next screen, select
Advanced Options.

6. On the next screen, select
Startup Settings. Click the Restart Button.

7. On the next screen, press the
Number4 Key.

The computer will start in
Safe Mode.

Click the
Arrow Icon.

Select the
Administrator account.