Attempting to change an Azure App Service Plan from Premium to Standard tier fails with: "Failed to change to App Service plan: Cannot use the SKU Standard with File Change Audit for site..."

I don’t usually provide Azure operational support because of my current role but I still have a few clients who reaches out to me when they have issues in case I am able to provide a quick answer and I absolutely welcome it as it continues to give me exposure to day-to-day operational problems. A recent question I received a couple days ago was one that I’ve come across in the past and felt it is worth writing a quite blog post about it to help anyone who may come across this.

Problem

You’re attempting to change an App Service Plan from, say, the Premium Tier to Standard Tier but the process fails with the message:

Failed to change to App Service plan: 'Cannot use the SKU Standard with File Change Audit for site <AppServicePlan>. See https://aka.ms/supported-log-types for more information.’

A quick search on the internet will return the following blog post: https://nexxai.dev/cannot-use-the-sku-basic-with-file-change-audit-for-site/, which outlines a series of steps with PowerShell cmdlets to remediate the issue. I’ve used this procedure in the past and it has worked for me but the post was written back in January 2021 and I suggest the solution below which uses the portal.azure.com GUI should be attempted before using PowerShell.

Solution

1. Login into portal.azure.com and navigate to the App Service.

2. Click on Diagnostic settings and look for a rule set that refers to App Service Audit Logs, then click on the Edit setting link:

3. With the settings of the rule displayed, scroll down the list and look for AppServiceAuditLogs, deselect it, save the configuration and confirm that you want to delete the setting:

Once the configuration has been updated, proceed and try changing the App Service Plan.

Hope this helps anyone looking for the solution to this issue.