Unable to reinstall OS X Yusemite on iMAC

Question

Level 1

8 points

Unable to reinstall OS X Yusemite on iMAC

Hi. I have an iMAC late 2009 running a Yusemite version. I decided to upgrade to High Sierra, so erased the Macintosh HD. Now I am not able to reinstall anything even the original Snow Leopard installation DVD is not useful. I have followed the process for similar problems but in vain. in one stage I receive the message that unmounting was not possible, when I try to erase the hard drive. Something must have gone wrong. There is another partition that I can'y change or erase or use for restore named Base something. How can I revive my iMAC? Thanks very much.

iMac Pro

Posted on Mar 30, 2020 12:56 PM

Reply

Answer 1

Kappy

Level 10

361,849 points

Mar 30, 2020 1:04 PM in response to Toopchi

How did you erase Macintosh HD? If you used the Recovery HD and Disk Utility, then you can still boot from the Recovery HD.

Install El Capitan or Later from Scratch

If possible, back up your files.

Restart the computer. Immediately, at or before the chime, hold down the Command and R keys until the Apple logo and progress bar appear. Wait until the Utility Menu appears.
Select Disk Utility from the Utility Menu and click on the Continue button.
When Disk Utility loads select the target drive (out-dented entry w/type and size info) from the Device list.
Click on the Erase button in Disk Utility's toolbar. A panel will drop down.
Set the partition scheme to GUID.
Set the Format type to APFS (SSDs only) or Mac OS Extended (Journaled.)
Click on the Apply button, then wait for the Done button to activate and click on it.
Quit Disk Utility and return to the Utility Menu.
Select Install OS X and click on the Continue button.

This should install the version of macOS you had installed - Yosemite (with an "O", not a "U".)

Reply

Answer 2

Toopchi Author

Level 1

8 points

Mar 31, 2020 12:23 AM in response to Kappy

Thanks for your prompt response. When I was following the steps for preparing my iMac for sale, I erased the Macintosh HD as the main hard drive. I was on the Disk Utility. Then restoring from OS X Base System failed. I inserted the Mac OS X Install DVD and it didn't work either.

I followed the steps you provided, and the results are shown in the screenshots (used iPhone camera) uploaded for your reference. Please note that I have not been using this computer for that past 2 years and have not any backup.

I would also appreciate it if you kindly advise on how to have a clean install after this current problem is resolved.

Thanks again.

Reply

Answer 3

Toopchi Author

Level 1

8 points

Apr 1, 2020 12:35 AM in response to Kappy

No, I didn't name any of the volumes. All this happened when I tried to reinstall from the original Mac OS X DVD (Snow Leopard) that came with the computer. Earlier, I tried to boot the computer from the installation DVD but failed. Then I followed your instructions by pressing cmd+R until the Disk Utility box opens.

I have taken new photos as per your advice, that are uploaded here.

Reply

Answer 4

Kappy

Level 10

361,849 points

Apr 1, 2020 10:04 AM in response to Toopchi

Thank you. Perfect pics. I now think I see the problem. When you open Disk Utility, I want you to select the sidebar entry you see below:

Now, click on the Partition button in the Disk Utility toolbar. You should see the following which you posted earlier. I have annotated changes you should make.

After you make the changes shown above, the Apply button should be active so click on it. This will configure the drive properly and with a more appropriate name. You should now be able to install Yosemite or whatever is on your installer DVD.

Reply

Answer 5

Kappy

Level 10

361,849 points

Mar 31, 2020 11:55 AM in response to Toopchi

I'm a bit puzzled. Did you name the volume (indented entry) Mac OS X Install DVD? It appears that you tried to install onto the main drive (500.11 GB ST...) and not on the volume which is what you should have selected. That is why the error was it could not unmount the disk.

From what are you booting the computer and running Disk Utility?

Reply

Answer 6

Kappy

Level 10

361,849 points

Mar 31, 2020 11:58 AM in response to Toopchi

When you post images please post each image separately. I have a hard time reading the information when they are so small and not sharp. I can enlarge them in Preview but they were hard to read. Before you post them check them out on your computer. Try to get them as sharp and clear as you can, it would be a big help. Keep the pics coming as they really help me see what you are doing.

Reply

Answer 7

Kappy

Level 10

361,849 points

Apr 1, 2020 1:46 PM in response to Toopchi

OK. It all looked right. It should have worked but Disk Utility could not unmount the drive. Of course, it cannot unmount the drive, it can only unmount the volume. Try this again but this time select the indented entry in the sidebar with the name, Mac OS X Install DVD. And, also start by clicking on the Erase button the the Disk Utility toolbar. I haven't used this old a version of Disk Utility in so long that I forget it doesn't work the same as the current one.

Reply

Answer 8

Toopchi Author

Level 1

8 points

Apr 1, 2020 3:04 PM in response to Kappy

Dear Kappy,

Million Thanks! I tried this and now in the process of installing the Snow Leopard from the installation DVD. Just started and hope it goes smoothly. Will keep you updated. Thanks again.

Reply

Answer 9

Toopchi Author

Level 1

8 points

Apr 1, 2020 1:28 PM in response to Kappy

Thanks for the response. I followed the steps and after clicking on Apply button, I receive an Error message (Partition failed). Photos are attached for easy reference. Thanks again.

Reply