I'm in the boat where I'm unable to upgrade beyond 7.1.4. As others have reported, UnRAID can't find the USB drive with anything beyond 7.1.4 on it. A console log of the boot process shows the system looking for a drive called "UNRAID" for 30 seconds and then giving up.

It appears that some sort of USB flash incompatibility was introduced post 7.1.4. I'm using a Verbatim 32GB drive, less than a year old.

So to my question: Is there a list of approved USB flash drives, since mine doesn't seem to be supported?

Thanks!

Bryan

Edited June 1Jun 1 by cowger
Marking as resolved

Are you sure your flash drive is actually labeled 'UNRAID' ?

Do you have a current flash backup?

Can you do a completely new install on that same flash drive and see if it will boot on your server? If not, will it boot on another computer?

7 minutes ago, trurl said:

Are you sure your flash drive is actually labeled 'UNRAID' ?

Do you have a current flash backup?

Can you do a completely new install on that same flash drive and see if it will boot on your server? If not, will it boot on another computer?

Thanks for the response. The flash is labeled UNRAID. It works just fine with 7.1.4.

And yes, I have a backup. Each time I've tried to upgrade the OS, I need to restore the flash to 7.1.4 and then the system boots. This been very consistent over the past many months and several different post-7.1.4 versions.

To your 3rd question, I just tried booting this flash in a different system, and it does, with both 7.1.4 and 7.2.4. I'm not sure what to make of that. This problematic behavior has existed across two different motherboards in my NAS system. I've tried both internal (baseboard) USB ports as well as the front panel ports. Hmmm....

Try the manual Install Method.

https://docs.unraid.net/unraid-os/getting-started/set-up-unraid/create-your-bootable-media/#manual-install-method

Edited March 1Mar 1 by Frank1940

1 hour ago, Frank1940 said:

Try the manual Install Method.

https://docs.unraid.net/unraid-os/getting-started/set-up-unraid/create-your-bootable-media/#manual-install-method

Thanks. Can you please elaborate on why you are suggesting this? The (automated) install/upgrade of the OS seems to be fine for a different machine, so does the manual install actually do something different that might fix this issue on my primary NAS server?

Just now, cowger said:

Thanks. Can you please elaborate on why you are suggesting this? The (automated) install/upgrade of the OS seems to be fine for a different machine, so does the manual install actually do something different that might fix this issue on my primary NAS server?

In the past, this method seems to work in some instances when the automated tool fails. Not sure why...

1 hour ago, Frank1940 said:

In the past, this method seems to work in some instances when the automated tool fails. Not sure why...

Okay, thanks. I don't believe that the automated tool is installing the new OS incorrectly. I believe there is something in the OS or, more likely, the bootloader that changed post 7.1.4. That OS boots every time for me. Any later OS doesn't. This happens on the exact same hardware, and others have posted here about the same behavior:

When this happens, the flash drive is typically not the problem; it's a compatibility issue between the kernel and the hardware being used, 7.3 may work again since it will use a very different kernel.

6 hours ago, JorgeB said:

When this happens, the flash drive is typically not the problem; it's a compatibility issue between the kernel and the hardware being used, 7.3 may work again since it will use a very different kernel.

Thank you, Jorge, good to know. I'll wait for 7.3 and give it another try then.

Cheers!

On 3/2/2026 at 12:28 AM, JorgeB said:

When this happens, the flash drive is typically not the problem; it's a compatibility issue between the kernel and the hardware being used, 7.3 may work again since it will use a very different kernel.

Well, unfortunately 7.3.x did not solve this issue. My system still hangs during reboot, looking for (and not finding) the flash drive.

I remain stuck back at 7.1.4. I'm still unsure if a different flash drive will solve this issue or not... and could really use some advice!!!

Thanks,

Bryan

7 minutes ago, cowger said:

Well, unfortunately 7.3.x did not solve this issue. My system still hangs during reboot, looking for (and not finding) the flash drive.

I can only imagine your frustration.... Try a "USB2" port-- you may have to consult the MB manual. (Some MB USB3 ports are not always handled well when used to boot Unraid and they tend to get 'lost' in the process. The source of the problem has never been identified.)

Edited June 1Jun 1 by Frank1940
added the "not" in this phase---- 'Some MB USB3 ports are not always '

13 minutes ago, cowger said:

My system still hangs during reboot, looking for (and not finding) the flash drive.

It's worth trying with a different flash drive using a stock install, no key needed, just to see if it boots.

1 hour ago, Frank1940 said:

I can only imagine your frustration.... Try a "USB2" port-- you may have to consult the MB manual. (Some MB USB3 ports are always handled well when used to boot Unraid and they tend to get 'lost' in the process. The source of the problem has never been identified.)

1 hour ago, JorgeB said:

It's worth trying with a different flash drive using a stock install, no key needed, just to see if it boots.

Thank you both for responding. I had tried different flash drives previously (7.2.x) with no result, so I didn't even think to try it again now. But... I'm now booted on 7.3.1, key is transferred, and I'm current on my software for the first time in 2+ years. Woohoo!!!!

Thanks again!!!