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applpal

Q: Cant 'Partition' new USB drive to make it bootable installer (to create external drive as startup disk)

Cant 'Partition' it. The Partition button is disabled surprisingly. Only 'mount' and 'partition' buttons are disabled. but 'First Aid' & 'Erase' is Enabled.
Just unboxed new 16GB USB3 drive to make it boot ready. ( Upgraded OS from Yosemite to El Capitan 10.11.2 and yesterday I could use 'Partition' command for Internal MacHD & created a test 50GB encrypted partition drive)

 

I want to do a fresh clean install, so I wanted  create this ext backup start up disk before erasing the internal macHD disk.

MacBook Pro with Retina display, OS X El Capitan (10.11.2), New Mac; Setting up req stuffs.

Posted on Dec 12, 2015 2:23 PM

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Q: Cant 'Partition' new USB drive to make it bootable installer (to create external drive as startup disk)

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  • by Barney-15E,Helpful

    Barney-15E Barney-15E Dec 12, 2015 7:14 PM in response to applpal
    Level 9 (50,082 points)
    Mac OS X
    Dec 12, 2015 7:14 PM in response to applpal

    How about Erase?

    Can you erase it and set it to OS X Extended (Journaled)? I think that will create it with GUID partition table.

    Then, you should be able to partition it into smaller chunks.

  • by TARDIS75a,

    TARDIS75a TARDIS75a Dec 12, 2015 6:07 PM in response to applpal
    Level 1 (0 points)
    Dec 12, 2015 6:07 PM in response to applpal

    my Seagate external 2 TB drive has had problems ever since I formatted it to Mac GUID Journaled format. Everytime I download photos from iCloud in full format, with plenty of space on the drive, the drive becomes un-writable and most of the time un-readable too.  I think I've formatted it about 6 times now. Going back and forth between ExFAT, FAT32 and HFS+.  Since icloud photos can only download to a Mac formatted drive, then the ExFAT and FAT32 formats do not work and my drive is therefore not able to work for the purpose I bought it.

  • by applpal,

    applpal applpal Dec 12, 2015 7:19 PM in response to Barney-15E
    Level 1 (12 points)
    Mac OS X
    Dec 12, 2015 7:19 PM in response to Barney-15E

    Good. Thank you. U r right. I did so with GUID option and it did so.
    I thought Erasing might have helped to make the USB boot ready. But I have not done aagin any partitioning after erase.  When I was trying to execute the command for boot-install from terminal after 'Erase', it said 'command not found'.

    Let me try partitioning now it first.

  • by applpal,

    applpal applpal Dec 12, 2015 7:27 PM in response to TARDIS75a
    Level 1 (12 points)
    Mac OS X
    Dec 12, 2015 7:27 PM in response to TARDIS75a

    Sorry to hear about 2TB HDD which is a helpful investment. But how come the last format action as GUID journaled partition table not helping it. Any bad sector might have generated for other inbetween 5/6 various format actions. If those were complete actions without interruptions, then this issue can be resolved i guess someway. Let us know if you got any solution. Might be here somebody can help.

  • by applpal,

    applpal applpal Dec 12, 2015 8:48 PM in response to applpal
    Level 1 (12 points)
    Mac OS X
    Dec 12, 2015 8:48 PM in response to applpal

    Quick ( happy) update!  I did the partition. But even after that command was not executing in terminal.

    Then tried re-partition again with 2 volumes with one as more than 8gb. and then command line. But failed the installer command.

    When I removed admin$ from the whole line then it worked .  Now it is 'copying installer files to disk.....'  Hopefully it will be successful within few mins. Thanks for partitioning idea after erase.