33 votes

How to create a bootable Ubuntu USB stick using OS X 10.10.2

Follow these steps to create an .img file from the .iso file you have, and then copy to the USB stick. This will also change the filesystem that is on the USB to make it bootable. Open the Terminal ...
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24 votes
Accepted

No bootable device USB 2.0 MacBook Pro mid 2014

Installing Windows 7 or 10 Pro 64 bit without DVD or Flash Drive If you are trying to install Windows 7 on a 2012 through 2014 Mac, then you should read my answer to this question. Special thanks ...
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17 votes
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Boot camp install of Windows 7 issue, no bootable devices

UPDATE An improved procedure for installing Windows 7 can be found at Installing Windows 7 Pro 64 bit without DVD or Flash Drive Note: The updated steps, for installing Windows 8.1 using the ...
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16 votes

Could not validate sizes – Operation not permitted. The operation couldn’t be completed. (OSStatus error 1.)

I think the "Operation is not permitted" may be caused by Disk Utility lacking the necessary admin privileges. sudo /usr/sbin/asr restore --source BaseSystem.dmg --target /Volumes/MyVolume --erase ...
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14 votes

How can I download the macOS Big Sur installer on a Mac which is already running Big Sur?

You can download the official macOS Big Sur installer from Apple by using the following steps: On your Mac, open the Mac App Store app, search for Big Sur and click on the Big Sur app to access the ...
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14 votes
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How can I download the macOS Big Sur installer on a Mac which is already running Big Sur?

How can I download the macOS Big Sur installer on a Mac which is already running Big Sur? I'm finding that since this Mac is already upgraded, I can't download it again. How can I get ahold of the ...
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  • 53.9k
10 votes
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Will bootable usb created by bootcamp on mac work with PC?

After reading through several stackexchange answers, I found steps that worked on this site. He walks you through how to format the USB stick so that Windows will recognize it, and how to use ...
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  • 116
10 votes

Mac won't boot from USB drive: Prohibited sign

It may be that boot-up from the USB flash drive is "prohibited" because your USB flash drive requires adjustment to the "ownership" settings. I learned this the hard way myself. ...
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  • 159
8 votes

Unable to install an OS on Mac (prohibited sign)

To start with your MacBook Air will not run Mavericks, so you can put that one aside as incompatible. As for Yosemite, the earliest possible version that will run on your model MacBook Air is ...
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  • 62.3k
7 votes
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My external boot volume won't startup all my Macs when it should

From what you’ve said, I agree it should work fine. My first guess would be to check the Startup Security Utility on the iMac Pro, a feature of the iMac Pro (and other T2 Security Chip enabled Macs) ...
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  • 62.3k
7 votes

Could not validate sizes – Operation not permitted. The operation couldn’t be completed. (OSStatus error 1.)

You can do it easily using ASR command You have to scan your downloaded image via following command sudo /usr/sbin/asr imagescan --source ~/Downloads/macOSUpdCombo10.15.7.dmg After scan you have to ...
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5 votes

How to create linux USB discs that do work on Apple Macs?

When first posted in 2013, this question never received an answer, because there is no answer. In other words, Intel Macs can not BIOS boot from flash drives. I make the BIOS boot assumption based the ...
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5 votes
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Issues creating Bootable USB for EL Capitan Public beta

I tried many things talked about here and on other top Google searches: Redownloaded (three times) Tried moving the .app to Desktop Changed permissions of .app Verified the .dmg with hdiutil Used ...
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5 votes
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How to create Catalina.app for creating bootable disk

If one is already running macOS Catalina, just open Terminal and use the following command to download the latest release of macOS: softwareupdate --fetch-full-installer Or to download a specific ...
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  • 53.9k
5 votes
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How can you create a valid/reliable disk image of APFS drives?

I FOUND THE SOLUTION to using Apple Disk Utility to create RELIABLE disk images of APFS drives. The ONLY path to make a viable re-usable disk image formatted as APFS in 3 simple steps is (though ...
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4 votes

How to create linux USB discs that do work on Apple Macs?

Check Ubuntu's tutorial how to create a bootable USB stick on macOS, where it is suggested to use Etcher app (open source) which can help to flash OS image to SD cards & USB drives. However, if ...
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  • 11.9k
4 votes

How to create a USB installer for multiple OS on an OS X system?

The way to do this is to create multiple partitions on the USB drive. There is a Tech Republic article that gives the full details on how to do this: http://www.techrepublic.com/article/pro-tip-...
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4 votes
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How to make a bootable disc in Yosemite?

Locate the .iso file you want to burn and place it on your Desktop: Navigate to to Disc Utility (Applications -> Utilities -> Disc Utility) Once Disc Utility is opened, drag and drop the .iso ...
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  • 1,014
4 votes

How to create a Mac bootable gparted or Parted Magic thumb drive?

The following steps have been tested on macOS Mojave 10.14.6 and I confirm I was able to boot GParted on a 2019 MacBook Air (with secure boot disabled). That being said, the keyboard and trackpad didn’...
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4 votes
Accepted

OS X 10.11 GM Candidate 1 left my Mac unable to boot

You do have a recent backup? If not this procedure will be substantially different. Backed Up? Use Recovery Mode If you boot into recovery mode using Command+R at startup can you proceed with an ...
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4 votes

Mac won't boot from USB drive: Prohibited sign

This also seems to be the behavior if your Mac is not compatible with the OS you are trying to install, which was not obvious to me. In my case, I was trying to install High Sierra or Mojave on a Late ...
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  • 141
4 votes
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Cloned disk from older MacBook not booting on new MacBook Pro

No Mac will boot to an OS older than itself, with the exception of models released right on the cusp of a new major OS version. The drivers for the newer model didn't yet exist.
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  • 101k
4 votes
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Installing macOS on a new HDD from USB drive stuck on grey screen with Stop sign

My old MacBook Pro is a mid 2009 model which is not supported by macOS Sierra. - Only MBPs Mid 2010 and later are supported. I created an bootable USB disk from El Capitan (which I re-downloaded ...
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  • 161
4 votes
Accepted

El Capitan bootable installer on Mac Mini - "A required download is missing"

You probably used an old macOS installer app to create your USB bootable disk. A lot of macOS installer apps downloaded before Oct 2019/Nov 2019 contain an outdated certification chain and thus are ...
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  • 64.1k
4 votes
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How to create a bootable OS X Snow Leopard USB drive?

Creating a USB Flash Drive Installer from a Snow Leopard ISO File Below are three methods. The first method, which involves the Disk Utility application, failed to work when tested using macOS ...
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4 votes

Macbook Air 2019 will not boot from USB or complete Internet Recovery, Exhausted options

Call Apple or chat online with service would be my next step. Ask for a mail in repair if available and convenient. #3 is really unlikely to be anything easy if you have charged it for 2 to 4 hours. ...
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  • 221k
4 votes

Mac not bootable, save files with other mac

The more valuable the files, the slower you should be and refrain from trying command line tools on your only copy of the drive. Test with a rented Mac first to be sure you have control of the system ...
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  • 221k
3 votes

Mac Backup Software that can run from a CD/DVD

This might be considered pure opinion rather than fact, but I'd say just dedicate a spare HD to it & set up Time Machine. I use both Win & Mac here, Macs backed to Time Machine & Win to ...
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  • 101k
3 votes
Accepted

Macbook Lion Recovery Disk Utilities cannot detect newly installed SSD

Boot into Recovery from the USB. Instead of opening Disk Utility, open Terminal instead. Run the command diskutil list to see that your drive is being recognised. It should list two disks, one being ...
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  • 1,448

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