External SSD won’t boot after power outage

[piscotikus]

I have a 5 year old iMac that I have been booting from an external SSD.

This weekend our power went out and the SSD drive gets stuck on a loading bar. I have let it go 24 hours and it’s till half way.

I was able to unplug it and boot from the internal drive.

I have a separate external drive for Time Machine.

How can I fix the external boot drive?

 

[pmiles]

Can you see the external drive in Disk Utility on the iMac if the you connect the drive to the iMac? I'm assuming that everything important is saved on the other external drive. My thought is that the drive got corrupted in a way to prevent it from booting. Meaning you would likely have to erase the drive and set it up anew. This of course is predicated on the idea that Mac can even see the external drive to allow you to do this.

Why are you booting from an external SSD versus the internal drive on the iMac?

Do you have access to a PC by any chance to see if it can mount/see the drive. Don't do this if you absolutely need the data on said drive as it may ask you to format the drive when it mounts. Just another way to see if the drive is functioning, if it's not mounting/booting for the iMac.

If disk utility can't see the drive, terminal may be an option.

See this for some commands to try:

Manage External Hard Drive with Terminal Commands on Mac

Many Mac users do not use terminal commands due to its non-graphical interface. But it is quite useful in

www.stellarinfo.com

 

[Bigwaff]

I have a 5 year old iMac that I have been booting from an external SSD.

This weekend our power went out and the SSD drive gets stuck on a loading bar. I have let it go 24 hours and it’s till half way

Hope you can resurrect the drive. Moving forward, consider using a UPS battery backup power supply, especially if your boot drive is external and USB bus powered.

 

[piscotikus]

Why are you booting from an external SSD versus the internal drive on the iMac?

When I first got the iMac, it was very slow brand new, andI had read that most of the lag was due to the internal drive not being solid state. Since using the external drive it's worked faster and had been ok.

Can you see the external drive in Disk Utility on the iMac if the you connect the drive to the iMac?

Yes I can. I'm running First Aid on the drive now. Thank you for this recommendation.