You may receive this error:
Error: Restore cannot proceed, some files are currently locked.
You will receive this message when trying to restore a QuickBooks company file that is currently open, or is still in use by QuickBooks, even if the company file is closed.
Resolving This Error
In QuickBooks, use File > Exit to close the application, then attempt to restore the company file.
If you are still having issues, open the Task Manager, and locate the process QBE32.exe and end it. Then restore the company file.
For help with using the Task Manager, refer to this Microsoft support article.