I dont know much about docker but can you get to the Web.config file.
Did you try turing on the Stdout log to see if anything is writen there ?
ie. In Web.config change stdoutLogEnabled = "false" to true
Thanks, the stdout automatically gets routed to the azure log stream which is handy, but it just shows lots of success messages about loading up this and that, all pretty typical looking progress for starting up a .Net web app, and then a subset of the same success messages again each time I restart the application, nothing errorish or advisory whatsoever.
You need a shell into the docker container to get at any of the filestore within it (well, as far as I know, I'm no docker expert either), but I had problems getting a shell running (which will be an Azure configuration thing), so couldn't check any config or try the suggested changes - and in the end it was supposed to be a quick alternative to just pointing the client at the online demo so I didn't want to spend much time on it.
The thing is though, I've set up nopCommerce a few times the traditional way and all's been fine, sometimes a bit of tweaking but all good and lots of info here and elsewhere to do that. My bug report / issue raise was more about the docker image possibly having a problem within that stops a vanilla brand new setup working - one of the main benefits about docker/containerisation is removing the need for tinkering with the nuts and bolts, the image is supposed to be a working self-contained lump of executable and configuration as-is, so in theory I should just need to point it at a SQL and off we go - and clearly the SQL connection was OK as it intitialised all the tables etc. just fine.
In any event the client has had a look at the standard online demo and has moved on now so I've deleted the container so I don't get charged any more for it, so the problem (and any evidence!) has gone now, I'm more just commenting in case anyone wants to check out the docker image for NOP as there may be a problem with it.
Oh, and to have a sly little dig at the 'Sequence contains more than one element' error possibly needing to be more helpful or ideally the installer tidying up after/before itself.
Thanks again for trying to help though :)