Sierra Install Fail

[Kashchei]

i just tried to install the Sierra GM and I got the following message:
MacOS could not be installed on your computer
An internal error has occurred
Quit the installer to restart your computer and try again

When I do this, it automatically tries to install the Sierra GM again, which again fails. I tried to short circuit this process and held down the option key at startup but I am not given an option for startup disks. So I'm stuck and can't use my machine for work tomorrow. Can anyone help me?

Edit:
I can access disk utility once the install fails and before the restart. It says that the HD on my machine is damaged and can't be repaired. This is odd since I ran disk utility just the other day and it was fine. I can also access terminal.

 

[Ebenezum]

1. Hopefully you have a backup made before installing Sierra?

If so you might want to install previous OS from the backup.

2. Disk Utility error is worrying, what does it say about SMART status?

If its failing you have to replace the drive.

 

[Kashchei]

1. Hopefully you have a backup made before installing Sierra?

If so you might want to install previous OS from the backup.

2. Disk Utility error is worrying, what does it say about SMART status?

If its failing you have to replace the drive.

I went ahead and restored from time machine. I didn't get a chance to look at the SMART status. Is there a chance that this will happen again--I really don't want to go through this again! Thanks for your help!

 

[grahamperrin]

stuck

Reset NVRAM.

 

[Ebenezum]

I went ahead and restored from time machine. I didn't get a chance to look at the SMART status. Is there a chance that this will happen again--I really don't want to go through this again! Thanks for your help!

Open Disk Utility and select internal drive, you can see SMART status at the bottom right corner. Keep in mind that Apple removed most of the information in El Capitan Disk Utility and it will not find all problems. If you have further problems you might want to use other software that shows more SMART information.

I am concerned about the message Disk Utility give you, can you test it again in Disk Utility?

 

[Lukeit]

Hi All, I wanted to share my experience, someone might find it helpful.
I'm on a late 2012 iMac 27 with fusion drive. Leap of faith on High Sierra... First installation attempt failed because, I think, I asked to upgrade to APFS. Installation process came to a halt and I was already worried about reinstalling from scratch with only backup on external drive (no Timemachine)
Switched my iMac off, restarted holding Command +R and restored via internet. Restore process was with 10.13 and not with what I was thinking it would have been 10.12
This time I obviously did not thick to upgrade the file system and after 40 minutes my machine was up and running with High Sierra and most importantly I did not have to reinstall anything apps and such as all was there untouched.