Hi,
Can you elaborate on your issue?
Is it a Local User account on your Windows, or a folder named Default in a Users folder on your drive?
If possible, can you take a screenshot of the issue and upload it here? Make sure to remove or hide personal information or credentials.
If you are attempting to delete those folders, I recommend stopping for now and not proceeding until we can identify which default folder you are referring to, as it may be a system folder used by Windows.
I look forward to your response.
Stay Safe!