Hello @EnterpriseArchitect
To authenticate an Azure Function with an on-premises Windows File Server, you can use the Azure File Share or Azure File Sync service.
These services allow you to create a connection between your on-premises file server and Azure, and then use that connection to access the files from your Azure Function. To authenticate with Azure File Share, you can use either a Shared Access Signature (SAS) or a storage account key.
You can find more information on how to authenticate with Azure File Share in the following link: Develop for Azure Files with .NET To authenticate with Azure File Sync, you can use Azure Active Directory (AAD) authentication. You can find more information on how to authenticate with Azure File Sync in the following link: Deploy Azure File Sync
Regarding your question about adding the AD DS service account username and password under the Azure Function, you can use the storage account key or SAS to authenticate with Azure File Share, and AAD authentication to authenticate with Azure File Sync. You do not need to add the AD DS service account username and password under the Azure Function.
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