macbook pro error could not unmount disk

I bought a brand new 2TB Seagate Expansion to backup my MacBook Pro before I updated it to the latest macOS. Most External Hard Drives Are Initiated with NTFSĭuring the last several years, I’ve used a few external drives, including a 500GB WD My Passport, 32GB Lexar flash drive, and a few others.

How to Partition an External Hard Drive on Mac.

How to Format an External Drive for Mac.

Most External Hard Drives Are Initiated with NTFS.

I'm sure that the bad sectors are indicative of a broader problem with the disk, so I'll keep an eye on that by looking at Disk Utility periodically. What a relief!Īs a last step, I ran Disk Utility Verify once more. It took eight hours, but my machine greeted me in the morning as I'd left if, pre-crash.

Restore Data Finally, I was able to restore my entire system from my Time Machine backup.

This time, the erase process (make sure you go into Security Options and select at least the first level of zeroing) was smooth, taking just a few hours for my 1TB drive. Reformat and 'Zero' the Drive (Attempt 2) After rebooting, holding the Option key while doing so, I selected my USB boot drive and loaded up Disk Utility again.As expected, I found the same errors that Disk Utility had reported.

Double-check in Terminal While I waited for the USB boot drive to finish creating on the other computer, I ran a file system check (fsck) from Terminal just to be sure.I found great resources at TechRepublic, MacWorld, another MacWorld page and TUAW to help with this process. I had a tough time finding a family member or neighbor with either a DVD-R or thumb drive with the requisite 8 GB of space, but a quick trip to Staples solved that problem. It's a good thing to have in your bag of tricks. I had another Mac with which to do this, but if you don't, I would highly recommend doing this while you can. I got a ' Couldn't Unmount Disk' error that made this clear to me. Reformat and 'Zero' the Drive (Attempt 1) You can't do this if you've launched Disk Utility from the partition you're zeroing.Here are the steps that I took to resurrect my sad Mac. When you erase your drive, you must select 'Security Options' and select at least the first secure option, which not only writes zeroes on the disc, but it also marks bad sectors as such so they would no longer be used. This was frustrating, because I had just done this to try to resolve the problem, but I missed a key step. Unless, of course, you can REALLY use a stethoscope to troubleshoot. For fans of skeumorphism, it's alive and well in the Disk Utility interface.

Macbook pro error could not unmount disk