Web Disk Disabled in Feature Manager

Our normal configuration is to disable web disk. We have a dedicated server client who wants to use it. The cPanel DAV Daemon is running, but Web Disk is flagged as disabled in the feature manager so I am unable to enable it. Although I'm sure I've found it before, I've gone through everything I can think of and can't see where to make a change to enable it. How do I get it enabled for Feature Manager?