I am in the process of upgrading our current Umbraco v8 environment to Umbraco v10. During this upgrade I have set up Azure Blob Storage for our media fields as described in this guide

After some searching I also modified the setup in AppSettings to include the line "ContainerRootPath": "" to account for our original Blob storage being built for v7

  "Umbraco": {
    "Storage": {
      "AzureBlob": {
        "Media": {
          "ConnectionString": "<connection>",
          "ContainerName": "mediacontainer",
          "ContainerRootPath": ""
        }
      }
    },
  }

And when I run the code directly from Visual studio to test it, everything works without issue. However, when running it through a local IIS site, the neither backoffice nor the site can load media files. All I get is a 404 response for every file in the media library I try. The log files show very little difference in the startup process - and nothing relating to media files.

The only real difference i have found in running through an IIS site, is that certain filespaths are directed to the bin folder. E.g. the log files are saved in MyProject/bin/umbraco/Logs/ instead of MyProject/umbraco/Logs/.

It is a really weird problem - seeing as the code and appsettings file are the same in both environments, but one can access media files, and the other can't.