Issue Cause

When you download the Eagle macOS installer and find that the file is displayed in BZ2 format instead of the normal DMG file, this is usually because the default method for opening DMG files in macOS has been altered by a third-party decompression tool. When the system mistakenly identifies the DMG file as a BZ2 compressed file, you will be unable to install the software normally.

Solution Methods

Method 1: Change the Default Application

Locate the downloaded DMG file in Finder
Right-click on the file and select "Get Info" (or use the keyboard shortcut Command + I)
In the "Open with" section, check the currently set default application
If it's not "Disk Image Mounter," click the dropdown menu and select "Disk Image Mounter"
Click the "Change All" button to set it as the default application for all DMG files

Method 2: Manually Select the Opening Application

Right-click on the DMG file
Select "Open With" from the menu
Choose "Disk Image Mounter" (the built-in system tool) to open the file

Important Notes

After completing the above steps, you should be able to properly mount the DMG file and install the software
If the issue persists, try downloading the installation file again
Avoid installing too many third-party compression tools to prevent file association confusion

Unable to Install Eagle on macOS: BZ2 File Issue Detected