If the Red Giant Application Manager relays that services are unavailable, and you've already tried restarting both the program and the system, try re-downloading and reinstalling using its latest installer available here for Mac or here for Windows.
- This is an especially advised step if you have recently updated your operating system (e.g. into OS X 10.15.2, or 10.15.3).
- Even if you had just downloaded and reinstalled the Red Giant Application Manager, you should still re-download and reinstall just to rule out any sort of corrupted installer/installation issues.
- Some issues and bugs related to the Red Giant Application Manager were fixed by its installer and its installation process, so unfortunately it is not enough to just update the RG Application Manager, which is why the re-download and reinstallation is advised.
If it still fails to work after a reinstallation, contact support.