1
Boot your PC into Safe Mode using these steps, are you able to delete those JAR files in Safe Mode.
Click the power button on your Start menu.
Press the Shift Key and click Restart
Your PC will boot into the Windows Recovery Environment
Go to Troubleshoot - Advanced Option - Startup Settings and click Restart
Upon restart, press 5 to enter Safe Mode
2
If you are still unable to delete the JAR files, please provide a screenshot of a file explorer window showing the JAR files and the exact folder location the JAR files are stored in.
Also, please provide a screenshot of the error you see when you try to delete the JAR files.