Troubleshooting "NotImplemented / Access is denied" error when integrating Azure App Service with Azure Virtual Network (VNet)
Are you configuring your Azure App Service to use a VNet? The regional VNet integration for an Azure App Service is a preview feature, and so comes with some quirks. One of the documented limitations of this preview feature is that "The feature is only available from newer App Service scale units that support PremiumV2 App Service plans." This has interesting implications as to how you need to deploy your App Service, otherwise you could end up with a rather perplexing pattern of errors. Read about how we came about this error, and how we ended up fixing it.