I give up. I have a brand new Roku Express and an older (2010 or so Samsung TV). When I followed the instructions, I got connected to my WiFi router. Then I was prompted to update the software. I have tried to do this a dozen or more times. I see a rotating icon and the progress indicator jumps from 0 to 48 or 49% and after 30 or 40 seconds it says "unable to update software", with error code 005. The only option is to try again, which I did. I power cycled everything ... No difference. There was a link that said for more help, goto go.roku.com/sofwareupdate. I went there and the only guidance I could find said that I might get error codes 001 thru 006, but it did not say what the error codes meant, so that wasn't helpful. I also saw that there is a way to update using USB. I went to the site that was mentioned and the first question was to select my brand of TV. The list did not include Samsung. There was no option to do anything if the TV brand could not be selected, so I was blocked from going any further. No idea what to do next. I do not have the option of going to a different network to try the update on and then go back to my home network, so I guess I am the proud owner of a device that is just an idle museum piece like my old floppy disk drives. I am thoroughly unpressed by Roku. An actual support site with which I could interact would be very nice. Asking Roku users to serve that role is not a very impressive solution, so I am thoroughly unimpressed by Roku.
I honestly don't know why Roku bothers having numbered codes when they don't tell you what they mean... welcome to the Roku world.
I can't offer much advice as the usual remedy is to use an alternate network. Are you sure your phone can't act as a hotspot?
As for USB updating, that's only for actual Roku TVs. Most of the devices that use a USB power adapter don't even have a real USB port (it's just for power) and even those that do don't allow for updating via the USB port.
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