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Scrubbed Drive - Catalina OS needed to Boot on StartUp -USB not recognizing!

Hi Gurus,


I'm trying to download Catalina to my Mac I accidently scrubbed clean... (yes, I paused before doing it and wound up inadvertantly scrubbing the drive clean...)


The USB I downloaded Catalina to isn't even being recognized by the Mac.


I'm holding down the command key and trying to get the boot to come up as an option and I keep getting the message no boot drive found.


I went to just clean out the hard drive because I'm giving it to a young family to use for the online classes for their kids and now I've made it nonfunctioning...


Can anyone tell me how to do this... the 50 windows I have open on my Windows PC have only gotten me to the point of downloading Catalina to a flashdrive successfully. Can't get the Mac to recognize it.


I cry Uncle, waving the white flag here, any suggestions by any chance??


Thank you!


[Link Edited by Moderator]




Posted on Feb 9, 2021 3:29 AM

Reply
Question marked as Top-ranking reply

Posted on Feb 9, 2021 1:05 PM

The USB stick needs to be formatted as Mac OS Extended (Journaled) on a GUID Partition Map.

And simply downloading the Catalina install app and sticking it on a USB does not mean you

can boot to the USB and install Catalina.


You need to do the on a mac. Read the instructions here,

How to create a bootable installer for macOS – Apple Support

Similar questions

9 replies
Question marked as Top-ranking reply

Feb 9, 2021 1:05 PM in response to NCR3208

The USB stick needs to be formatted as Mac OS Extended (Journaled) on a GUID Partition Map.

And simply downloading the Catalina install app and sticking it on a USB does not mean you

can boot to the USB and install Catalina.


You need to do the on a mac. Read the instructions here,

How to create a bootable installer for macOS – Apple Support

Feb 9, 2021 3:58 AM in response to NCR3208

NCR3208 wrote:

Hi Gurus,

I'm trying to download Catalina to my Mac I accidently scrubbed clean... (yes, I paused before doing it and wound up inadvertantly scrubbing the drive clean...)

The USB I downloaded Catalina to isn't even being recognized by the Mac.

I'm holding down the command key and trying to get the boot to come up as an option and I keep getting the message no boot drive found.




Hold the Option key to pull up the StartUp Disk Manger ....



If no resolve reinstall though the Internet Recovery—

How to reinstall macOS from macOS Recovery - https://support.apple.com/en-us/HT204904



What to do before you sell, give away, or trade in your Mac ...


Feb 9, 2021 11:08 PM in response to NCR3208

No Apple do not provide its installers through other means only via download.


Do you have another mac you can use to create the bootable installer.


If you only have the one mac you can try Apples Recovery Servers to reinstall the OS.

How to reinstall macOS - Apple Support Read the instructions for Intel based macs.

When downloading from Apple Recovery Servers use a cabled connection to your router

for stability and speed. Do not use other devices that share the same internet connection

while the mac is downloading.


Never erase your mac without having the means to reinstall an OS to hand,

make the bootable USB installer before you erase.

Feb 12, 2021 1:36 PM in response to leroydouglas

Thanks, I wrote that wrong... I have done it holding the Alt/Option key and gotten the no boot drive found. If I hold the power button looking for the Utilities Window in Mac Recovery I get the same as if just holding the power to boot up - a flashing file with a question mark. About to lose my mind over this... **** Have tried this to create the operating system **** and the flash drive isn't recognizing the boot drive or the OS files. Don't know enough about Mac to fix this craziness and don't have another Mac to download the boot - everything else is Windows 10.


I really appreciate all of the tips - Apple Community is the best!




[Link Edited by Moderator]

Feb 12, 2021 1:36 PM in response to Eau Rouge

No other Mac... tried the reinstall MacOS from Apple Support. Lesson definitely learned on this one - wasn't planning on scrubbing the thing just bringing it back to factory settings with the upgraded OS Catalina I had gotten it up to... obviously followed the WRONG tutorial online and have since learned but now I have to get it back running... if possible.

Feb 12, 2021 6:50 PM in response to NCR3208

Do you have an Intel based mac, then you will only get to the Recovery Drive> Utilities screen by pressing and holding the Command and R keys.

It is best to do this with the mac connected to your router via cable.

Select Disk Utility press Continue.

Click View in the menubar and select Show All Devices.

In the left hand column select the Disk (probably called Apple SSD…) not any of the indented Volumes.

Click Erase.

Give the Disk a name.

Format: Mac OS Extended (Journaled) or APFS.

(choose Mac OS Extended (Journaled) if this mac came preinstalled with an OS earlier than Mojave, choose

APFS if it came preinstalled with Mojave or Catalina.)

Scheme GUID Partition Map

Click Erase.

When Done quit Disk Utility.

Click on Install OS press Continue.

Th installation process should start follow the prompts.


I haven't come across any one who has successfully made a bootable USB for mac on a Windows machine.

Scrubbed Drive - Catalina OS needed to Boot on StartUp -USB not recognizing!

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