This week I had to address a upload image to blob application that I had built in my development environment, was working fine, but needed to be configured to work in production.  For the application overall, I used Azure Samples for Upload Image to Storage (built in .NET Core).  In it, the configuration in appsettings.json looks like this:

"AzureStorageConfig": {
    "AccountName": "",
    "AccountKey": "",
    "ImageContainer": "images",
    "ThumbnailContainer": "thumbnails"
}

Account Name account name and AccountKey are easily found in Azure Portal, for container I used Azure Storage Explorer just so I could get a full look at the container and its blobs.  The problem was, in my development environment I was uploading DIRECTLY to container.  In the example above, I was uploading to the “images” container.  In my Production environment, though, my ImagesContainer had two folders:  images/small and images/large.  I tried to change the “ImagesContainer”:”images” to “ImagesContainer”:”images/small”, “ImagesContainer”:”images\small” and no go.  Requested URI not found.