Merge pull request #212362 from kof-f/patch-56

Adding pointer to auth error

Author: prmerger-automator[bot]

articles/virtual-machines/linux/image-builder-json.md

@@ -1150,6 +1150,9 @@ properties: {
 - **The stagingResourceGroup property is specified with a resource group that exists**
 
   If the `stagingResourceGroup` property is specified with a resource group that does exist, then the Image Builder service will check to make sure the resource group isn't associated with another image template, is empty (no resources inside), in the same region as the image template, and has either "Contributor" or "Owner" RBAC applied to the identity assigned to the Azure Image Builder image template resource. If any of the aforementioned requirements aren't met, an error will be thrown. The staging resource group will have the following tags added to it: `usedBy`, `imageTemplateName`, `imageTemplateResourceGroupName`. Pre-existing tags aren't deleted.
+  
+> [!IMPORTANT]
+> You will need to assign the contributor role to the resource group for the service principal corresponding to Azure Image Builder's first party app when trying to specify a pre-existing resource group and VNet to the Azure Image Builder service with a Windows source image. For the CLI command and portal instructions on how to assign the contributor role to the resource group see the following documentation [Troubleshoot VM Azure Image Builder: Authorization error creating disk](https://learn.microsoft.com/us/azure/virtual-machines/linux/image-builder-troubleshoot#authorization-error-creating-disk)
 
 - **The stagingResourceGroup property is specified with a resource group that doesn't exist**