You can enable Frontpage Extensions right from your DotNetPanel.
Login to DotNetPanel and click on your Package.
Now click on your Website from Hosting Space Menu and then Website Properties.
You should an interface as below:

Next, click on Front Page Tab.
Type the name and password of FrontPage account in the FrontPage Account and FrontPage Password boxes.
Click Install button.
FrontPage status will now be changed to Installed.