Use built-in OS encryption or access control features
Set folder permissions so only authorized users can open it
Create a password-protected archive with ZIP, RAR, or 7z
Use third-party folder locking software
Encrypt the folder with BitLocker, FileVault, or similar tools
Store sensitive files inside an encrypted container
Use a strong, unique password
Enable two-factor authentication on the account
Keep backups of important files in a secure location
Update the operating system and security software regularly