Phoenix RC is no longer supported
Horizon Hobby has abandoned Phoenix RC in 2018. This does not mean that it is no more running fine. Just that you need additional efforts to install it. You can still run Phoenix. Just because there will be no further upgrades is no reason to suddenly abandon it.
- to download all files of Phoenix RC, use this mirror
- to fly online in Phoenix RC using network mode with more pilots, use this VPN trick
Phoenix RC sim running on Windows 10
In windows 10, you may be missing the DirectX 9 runtime d3_dx43.dll library file. Use this Microsoft link to a download which scans your PC and installs all missing Direct X (and earlier) library files missing on your PC.
You could switch to AccuRC, its far more realistic than phoenix for helicopters and has a lot of the current models in it too. Or Realflight 9 or Aerofly