Need Help with Reverting to Yosemite

[gthorson]

So I installed El Capitan and it mostly works fine. However, I can't access a USB receiver that I use in teaching my classes (TurningPoint 5.0). It appears that USB recognition has been a problem for some people on all the releases of El Capitan. FYI, I'm currently on the GM Candidate.

I think I need to revert back to Yosemite so that I can use this critical functionality. Although I made a backup using Yosemite in Time Machine, I deleted it when I backed up to install the GM.

Is there any way that I can still back up to Yosemite, or do I need a Yosemite backup?

Thanks for any help you can offer!

 

[Shirasaki]

Before you plan to downgrade to Yosemite, you need a Yosemite install disk, because installing Yosemite or restoring Yosemite time machine backup in El Capitan is not supported.

 

[w0lf]

Pretty sure just installing Yosemite over El Capitan should work.

 

[Shirasaki]

Pretty sure just installing Yosemite over El Capitan should work.

But I have tried this and it doesn't work under El Capitan. Either in standard mode or recovery mode.

 

[Lolito]

But I have tried this and it doesn't work under El Capitan. Either in standard mode or recovery mode.

you can even erase el capitan and install tiger. of course it is possible.

 

[gthorson]

So I'm failing miserably at this. I erased my hard drive and rebooted, but when I select the option to install OS X, the only option is El Capitan. How do I make a Yosemite install disk? I have three Macs, but all are already upgraded to El Capitan, and all of my backups are also El Capitan.

And just to clarify, if I do create a Yosemite install disk, can I boot to it, install Yosemite, and then restore my backup made with El Capitan?

Thanks again!

 

[gthorson]

Might it otherwise be possible to create a new partition, install Yosemite on it, restore everything to the new partition, and then delete the old partition?

 

[Shirasaki]

So I'm failing miserably at this. I erased my hard drive and rebooted, but when I select the option to install OS X, the only option is El Capitan. How do I make a Yosemite install disk? I have three Macs, but all are already upgraded to El Capitan, and all of my backups are also El Capitan.

And just to clarify, if I do create a Yosemite install disk, can I boot to it, install Yosemite, and then restore my backup made with El Capitan?

Thanks again!

You can create a Yosemite install disk on El Capitan.
However, you cannot restore backup created in El Capitan.

 

[tywebb13]

Not sure about that.

I had a bit of a disaster with my installation of the GM via bootable usb. It got half way through then quit with errors. It might have been a faulty usb.

When I ran diskutil list it apparently created 12 disks on my drive which was weird.

I couldn't boot into DP8 anymore.

I had a backup of DP8 and I had a yosemite bootable usb, and decided to use it to restore my El Capitan DP8 backup. This did work, so I don't know where you got your information that it wouldn't work. And I used the yosemite one because I suspected the El Capitan one I made was faulty. But I knew the Yosemite one wasn't because I have used it for installations before.

Then I ran the GM installer file again, but this time from the desktop, not a usb and this successfully updated DP8 to the GM. It was a roundabout way but I got there in the end. And the first thing I did after that was to backup the GM!

 

[navaira]

The 12 partitions thing is normal, Linux install USB does the same thing. Not that I know what it's for. But it's normal.

 

[tywebb13]

Well not being able to boot into DP8 after the GM installer quit is not normal. It should have let me boot up DP8 again. It probably had a partial update leaving the rest of the system hanging. So I wiped the drive, restored from backup and then updated to the GM.

But I used a yosemite bootable usb to restore my el capitan dp8 backup.

 

[simonsi]

but all are already upgraded to El Capitan, and all of my backups are also El Capitan.

You do understand what a backup is for right? You should upgrade ONE machine, then test your critical functions, then roll out to your other machines and only delete the old OS backups once you are certain you won't need them. That assumes it is sensible for you to be upgrading to pre-release versions in any case...

 

[gthorson]

You do understand what a backup is for right? You should upgrade ONE machine, then test your critical functions, then roll out to your other machines and only delete the old OS backups once you are certain you won't need them. That assumes it is sensible for you to be upgrading to pre-release versions in any case...

Yep. Everything appeared to work well, but my classes didn't start until last week. The software worked fine, but I neglected to test the USB.

I deleted the backup after I tested the software, but I didn't ever contemplate that there could be a systematic problem with the recognition of USB devices. I naively thought this would be a hardware rather than a software issue.

From Google searches, it looks like this is a rather large problem with El Capitan. It looks as though I might have better luck trying to get the USB to work under El Capitan. But these fixes are a bit complex for me.