There is two methods to try and delete all of the Phantasy Star Online 2 Installations.
Method 1: Built-in Windows Cleanup
This is the safest method, and the steps are as follows...
- Open up the Settings Application for Windows 10. This is the Gear Icon that appears in the Start menu.
- Navigate to System
- Navigate to Storage.
- Click on the "Temporary Files"
- Make sure that "Delivery Optimization Files" is checked.
- Click on "Remove Files", and wait. This can take a while since there may be more than 50gb of files involved.
Method 2: use command prompt
Warning: This method is intended for Advanced users only. Do not attempt this method unless you are familiar with working in command line environments.
- Open up an administrative command prompt.
- Navigate to the Windows Store Automated Backup folder ( The default location is c:\Program Files\WindowsApps\MutableBackups ).
- List the directories in the path. The old folders for Phantasy Star Online 2 should start with "100B7A24.oxyna".
- use the takeown command to recursively take ownership of each folder one by one.
- use the rmdir command to recursively erase each folder one by one.