This article will show you How to Password Protect a Directory in Windows Plesk
Step 1. Log into Plesk
Step 2. Click on Password-Protected Directories
Step 3. Click on Add Protected Directory
Step 4. Enter the name of the Directory you want to protect, then click Ok
Step 5. The directory is now protected, however we now have to create at least one user that can access it. Click on directory name
Step 6. Click Add a User
Step 7. Give the new user a username and password, then click Ok.