To edit a PowerPoint file protected by IRM, you typically need to open it in the desktop version of Microsoft PowerPoint. Here's how you can do that:
Make sure you have the desktop version of Microsoft PowerPoint installed on your computer.
Open the PowerPoint application.
Go to "File" and select "Open" to browse for the protected PowerPoint file.
Locate and select the file you want to open.
If the file is protected by IRM, you will likely be prompted to sign in with the appropriate credentials or verify your identity to access and edit the file.
Once authenticated, you should be able to open and edit the file in the desktop version of PowerPoint.