Here is how to enable directory security for your domain(s):
Log into your HELM control panel.
Click the domains icon from the user's menu and select the domain from the list.
3. Click File Manager icon from the domain menu, and create a new folder with the name you wish. (Note: This step can be skipped if the folder already exists in the web root.)
Under the Domain Menu, click the FTP Accounts icon. Add a new FTP account with the desired user name and password. Choose the folder that should be protected and click Save. (Both Read and Write dialog boxes should be checked.)
Log into your VPS or dedicated server via Remote Desktop. (Note: Shared customers will have to submit a support ticket to complete this part.)
Open the IIS manager and browse to your website folder.
Right click on the folder and choose properties.
Click the Directory Security tab, then click the Edit button for "Authentication and access control".
Uncheck "Enabled anonymous access", and check "Basic authentication", click OK.
Browse to the secure folder URL and test the login.
Please contact support if you have any questions.