If you want to use a new hard drive that was pre-formatted for Windows, can you just go directly to 'format' or do you have to first erase the drive (even though there are no files on it)?
Thanks.
(Probably shouldn't make any difference, but the drive, though never used, isn't of recent vintage.)
ddow77 wrote:
Thanks. However, when I click on Erase, the format options that appear don't include the APFS file system -- just Mac OS Extended (Journaled) and Mac OS Extended (Case-sensitive, Journaled) as well as the two PC options.
Why would APFS not appear as an option?
Because the drive partition map is "Master Boot Record". You have to change the partition map to GUID, and then you can choose APFS or MacOS Extended.
Set View->Show All Devices
Select the drive itself (not the volume inside it)
Click Erase
In the Scheme popup choose GUID
ddow77 wrote:
Thanks. However, when I click on Erase, the format options that appear don't include the APFS file system -- just Mac OS Extended (Journaled) and Mac OS Extended (Case-sensitive, Journaled) as well as the two PC options.
Why would APFS not appear as an option?
Because the drive partition map is "Master Boot Record". You have to change the partition map to GUID, and then you can choose APFS or MacOS Extended.
Set View->Show All Devices
Select the drive itself (not the volume inside it)
Click Erase
In the Scheme popup choose GUID
I've seen a couple of drives that needed erasing to ExFAT before it would take take any other format.
Just checking, are yoiu...
In Disk Utility>View, select Show all Devices, highlight the top left entry for that drive?
BDAqua wrote:
… highlight the top left entry for that drive?
Thanks, yes that was the problem, I selected the one below, which I thought was the correct one for the 'drive'.
I run First Aid on the latter, so I've always assumed the top entry was, if more than just a label, for something else (I don't know what).
I know I'm a bit late here, but you should always erase the whole physical drive with Disk Utility on macOS, but the physical drives are hidden by default these days. Here is an Apple article with instructions:
Erase and reformat a storage device in Disk Utility on Mac - Apple Support
I always erase (or Windows/Linux OS, I will first delete all partitions, then partition & format) the whole physical drive to make sure the OS I'm using is happy with the drive layout. Too many times you may receive odd partition layouts from the factory (some may be hidden) while some drives may contain manufacturer's codes hidden on the drive which can sometimes cause problems with some operating systems. Unfortunately Apple makes these things a bit more difficult than they really need to be.
You nailed it exactly. Thanks!
Thanks. However, when I click on Erase, the format options that appear don't include the APFS file system -- just Mac OS Extended (Journaled) and Mac OS Extended (Case-sensitive, Journaled) as well as the two PC options.
Why would APFS not appear as an option?
Also, I assume the drive icon to be selected for formatting is the indented one, not the top one -- or doesn't it matter?
(i.e., the "USB External Physical Volume" -- the lower indented option, not "Disk" -- the unindented upper option)
Mac OS Mojave (10.14.3)
2012 MacBook Pro
Erase & Format are interchangeable terms in Disk Utility, only very, very rarely would you need to Secure Erase the drive.
👍
Does a new hard drive that's pre-formatted for Windows have to be "erased" before formatting for a Mac?
