.i++ file: how to open it on Windows

2 Windows apps register the .i++ extension. Install one of them to open the file with a double-click.

• 
  Arduino IDE

  Open-source electronic prototyping platform enabling users to create interactive electronic objects.

  Open source 2.3.10 494.3K ↓ ★ 3.3K
• 
  Arduino IDE RC

  Arduino IDE (RC version)

  Open source 2.0.0-rc9.3 ★ 3.3K

Related guide: Change the default app for a file type in Windows