You've deleted the Billings Pro Server Admin application without turning the server Off. When you attempt to install it again, the installer displays a message "Please ensure Billings Pro Server is turned Off". You're now unable to access the application as a result.
Why is this problem occurring
Even though the application has been deleted all the background processes are still running.
- Open the Billings Pro Uninstaller located in the /Applications/Utilities/ folder.
- Check "Server Admin Application" and "Server Support Files".
- Click Uninstall then quit the Billings Pro Uninstaller once complete
- Attempt to install Billings Pro Server Admin again.