Adding a tip (#3780)

Author: stevewhims

hub/apps/develop/windows-app-restore.md

@@ -2,7 +2,7 @@
 title: 'Windows app restore: maximize the value of your app'
 description: This topic defines the tenets of Windows app restore that will enable your app to deliver the best backup and restore experience it can.
 ms.topic: article
-ms.date: 05/18/2023
+ms.date: 09/21/2023
 keywords: Windows, App, SDK, Windows app restore
 ms.author: stwhi
 author: stevewhims
@@ -58,6 +58,9 @@ For more info about the best practices of storing app data, see [Store and retri
 
 Windows introduced [known folders](/windows/win32/shell/known-folders) with Windows Vista. Since that time, users have come to expect that they can find the content they create with their apps in those locations. Writing user-generated content to those locations has the added benefit that OneDrive will back up those folders, if enabled, to ensure they're available to the user on their new PC (see [Back up your folders with OneDrive](https://support.microsoft.com/office/back-up-your-folders-with-onedrive-d61a7930-a6fb-4b95-b28a-6552e77c3057)). By using standard Windows APIs to write your user-generated content to the known folders, you're improving the user experience, and decreasing friction in adopting your app.
 
+> [!TIP]
+> We advise not to store machine-specific data in known folders. That's because those user-specific folders travel with the user between machines. So storing machine-specific data can result in conflicts and problems when users use your app on multiple machines, or after an upgrade.
+
 ## Best practices for unpackaged apps
 
 If you can't package your app, then be sure that your installer implements the recommendations below. That will ensure that it's possible to backup and restore the **Start** menu shortcuts that enable installing on a new machine that's restored from backup.