no mountable file systems
Hi, I am trying to download Sage on my Mac running OS X EL Capitan (10.11.6), and every time I try to open the disk image I get the error "no mountable file systems." This has persisted when I download the app.dmg as well as the .dmg, restarting my computer, creating a new account on my computer, etc., as well as trying to open it in Terminal. Has anyone experienced this?
Since macOS 10.11 is no longer getting any security updates, a more up-to-date OS is recommended.
If updating the operating system is not an option for some reason, I would try
or if that fails,