I have a 2006 Mac Pro (MacPro 1,1) with 4GB RAM running OS X Lion (10.7.5)

I've been using this link: https://support.apple.com/en-us/HT210717, to try and upgrade my computer. I've successfully downloaded the file (InstallMacOSX.dmg) from step 4, but whenever I try to open the file to install it onto my computer, my computer tells me that it can't read it due to it not being recognizable.

enter image description here

I've tried using disk utility to open it via Image>Verify, but it still didn't open it for the same reason. What can I do?

  • 4
    Which Mac do you have specifically?
    – Allan
    Apr 6, 2020 at 4:20
  • It's a Mac OS X, Version 10.7.5, a Lion. I'm not sure how else to describe my computer apart from the processor and memory found in "About This Mac"
    – Aluna
    Apr 6, 2020 at 17:14
  • Figured you had Lion, but we need to know which Mac model, so yes, the info from "About this Mac" would be really helpful
    – Allan
    Apr 6, 2020 at 18:13
  • Mac Pro, Software: Mac OS X Lion 10.7.5 (11G63b), Serial #: RM6431Y2UQ2, Processor 2 x 2.66 GHz Dual-Core Intel Xeon, Memory 4 GB 667 MHz DDR2 FB-DIMM, hope this helps at all
    – Aluna
    Apr 6, 2020 at 19:02

1 Answer 1


Your Mac is not compatible.

The Mac Pro 1,1 was released in 2006. Yosemite requires the Mac Pro 3,1 (2008) or later. Unfortunately, you are at the latest version of OS X that your Mac will support. See EveryMac.com for full details:

This system can run the last version of OS X 10.7 "Lion" if upgraded to at least 2 GB of RAM. However, although it has a 64-bit processor, it has a 32-bit EFI and cannot boot in 64-bit mode. It also does not support "OpenCL" running the default video card or the other build-to-order video cards that were offered via custom configuration. Please also note that OS X Lion is not capable of running Mac OS X apps originally written for the PowerPC processor as it does not support the "Rosetta" environment.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .