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Not Able to Read Ext. HDD
- Thread starter krawfo
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HobeSoundDarryl
macrumors G5
New drive?
Formatted for Mac?
I believe Master Boot Record is a format to make it work with Windows PCs. I'm guessing this is probably a brand new drive you've purchased, pre-formatted for Windows. If so, format it for Mac and you should be fine.
If you need it to work on BOTH Mac and PCs, format it as ExFAT and that should work great for both.
Formatted for Mac?
I believe Master Boot Record is a format to make it work with Windows PCs. I'm guessing this is probably a brand new drive you've purchased, pre-formatted for Windows. If so, format it for Mac and you should be fine.
If you need it to work on BOTH Mac and PCs, format it as ExFAT and that should work great for both.
Last edited:
Is this a brand-new drive, just out-of-the-box?
Or... is it an older one?
As Hobe mentioned...
IF it's brand new, your "first step" should be an ERASE & REFORMAT to Mac format.
It's a platter-based hard drive, right?
In that case, erase it to "Mac OS extended, journaling enabled, GUID partition format".
Also known as HFS+.
HOWEVER... and this is a special case... if it's going to be used for a time machine backup, erase to APFS, GUID partition format. APFS is now required for tm backups, I believe (I don't use tm).
Hmmmm....
IF it's a drive that you've already been using for a while, I'm thinking that the "Master Boot Record" (as revealed by disk utility) could be a problem, because that's a "PC standard".
If disk utility won't repair it and get it mountable, you might try to scrounge up an old copy of "Drive Genius". Try running the repair/rebuild option on the drive.
If THAT doesn't work...
... maybe you ought to take it to a PC and see if there are any utilities there that can help.
Or... is it an older one?
As Hobe mentioned...
IF it's brand new, your "first step" should be an ERASE & REFORMAT to Mac format.
It's a platter-based hard drive, right?
In that case, erase it to "Mac OS extended, journaling enabled, GUID partition format".
Also known as HFS+.
HOWEVER... and this is a special case... if it's going to be used for a time machine backup, erase to APFS, GUID partition format. APFS is now required for tm backups, I believe (I don't use tm).
Hmmmm....
IF it's a drive that you've already been using for a while, I'm thinking that the "Master Boot Record" (as revealed by disk utility) could be a problem, because that's a "PC standard".
If disk utility won't repair it and get it mountable, you might try to scrounge up an old copy of "Drive Genius". Try running the repair/rebuild option on the drive.
If THAT doesn't work...
... maybe you ought to take it to a PC and see if there are any utilities there that can help.
Maybe this can help too:
Disk Drill - Top-Rated Data Recovery Tool for Windows & Mac
Disk Drill is a powerful data recovery software for Windows and Mac. It can recover lost files from any type of storage device, including hard drives, USB flash drives, memory cards, and more.
It's also in Setapp what has a free trial period.