How do you reinstall MacOS without another Mac?

[Sir Dude]

I've got an old 2009 Mac Pro that was completely wiped from previous hijinks. I've got a new SSD that I'm trying to reinstall MacOS onto but on top of having no real idea of how MacOS works (I've never used one before) Google isn't helping with reinstalling MacOS onto it. I know it helps to have another Mac device on hand to perform some reinstall/repair process, but I don't have one available. I've got a flash drive I can use, but that's about it. How do you reinstall MacOS without another Mac?

[Zando_]

Hold CMD + I when it boots up to boot into Internet Recovery. Or CMD + R (regular recovery mode keybind, but it will boot to Internet Recovery if no OS is present). It will usually try and download the launch OS though, which can be annoying to upgrade from. On my mid-2012 MBPs that was Mac OS X Mountain Lion if I booted to Internet Recovery with no OS present. 

[SpookyCitrus]

You can use a Windows computer(if you have one) to make a MacOS install drive using a 32GB or larger flash drive. Then you would just hold option when turning on the Mac computer with the flash drive plugged in. When the boot options pull up you would click the MacOS installer off of the flash drive and it will walk you through the install process.

 

If it's a 2009 Mac computer you're going to be limited to MacOS El Capitan. Which just as an FYI isn't really good for much these days. You're going to be very limited on what a Mac this old can be used for.

[Agall]

1 hour ago, Sir Dude said:

I've got an old 2009 Mac Pro that was completely wiped from previous hijinks. I've got a new SSD that I'm trying to reinstall MacOS onto but on top of having no real idea of how MacOS works (I've never used one before) Google isn't helping with reinstalling MacOS onto it. I know it helps to have another Mac device on hand to perform some reinstall/repair process, but I don't have one available. I've got a flash drive I can use, but that's about it. How do you reinstall MacOS without another Mac?

I wouldn't be surprised if you're SoL since I remember a couple of years ago running into an issue with older Macs that didn't have a supported OS available to them at all. Apple basically clearing out older OS's that the recovery environment has access to.

[Sir Dude]

On 3/20/2024 at 1:42 PM, SpookyCitrus said:

You can use a Windows computer(if you have one) to make a MacOS install drive using a 32GB or larger flash drive. Then you would just hold option when turning on the Mac computer with the flash drive plugged in. When the boot options pull up you would click the MacOS installer off of the flash drive and it will walk you through the install process.

 

If it's a 2009 Mac computer you're going to be limited to MacOS El Capitan. Which just as an FYI isn't really good for much these days. You're going to be very limited on what a Mac this old can be used for.

Where do I go to actually do that? I couldn't seem to find anything that wasn't sketchy. And I don't actually need to use the Mac. I'm just trying to make a Windows server PC, I'm broke af and this is the most powerful computer I own. I just need MacOS to hand the hardware over to Windows because just throwing a Windows installed SSD into the machine didn't work last time I tried.

[SpookyCitrus]

43 minutes ago, Sir Dude said:

Where do I go to actually do that? I couldn't seem to find anything that wasn't sketchy. And I don't actually need to use the Mac. I'm just trying to make a Windows server PC, I'm broke af and this is the most powerful computer I own. I just need MacOS to hand the hardware over to Windows because just throwing a Windows installed SSD into the machine didn't work last time I tried.

If I'm remembering correctly, if it's an intel based mac, you should just be able to use a USB drive to install Windows onto it directly. You don't even need to have MacOS installed.

[ToboRobot]

On 3/20/2024 at 3:28 PM, Sir Dude said:

I've got an old 2009 Mac Pro that was completely wiped from previous hijinks. I've got a new SSD that I'm trying to reinstall MacOS onto but on top of having no real idea of how MacOS works (I've never used one before) Google isn't helping with reinstalling MacOS onto it. I know it helps to have another Mac device on hand to perform some reinstall/repair process, but I don't have one available. I've got a flash drive I can use, but that's about it. How do you reinstall MacOS without another Mac?

Turn the mac on and press and hold the option/alt key down to select the boot device.

It's a computer, so you need to find the CD/DVD with the OS and drivers for that computer or get a copy of the operating system and install it.

You can also run linux on it via the same process.