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"Microsoft has been weaving OneDrive more deeply into Windows with each update, and the upcoming Windows 10 feature update (build 17720) will continue the trend. An updated version of Microsoft Storage Sense will automatically back up content to OneDrive, and it may even remove the local version of the file to save space. This could be great for smaller disks, but you can disable Storage Sense if you want to manage your drives manually.
In the new version of Windows 10, Microsoft wants Storage Sense to operate as a “silent assistant” that you don’t have to babysit. As you use your computer and generate new files, they’ll be trickled up to OneDrive for safekeeping. That part isn’t new—the improvements come in what happens to the local files afterward. When you don’t use a file for some period of time (the default is 30 days), Windows can remove the local copy and replace it with a placeholder icon. Microsoft calls this process “dehydration.”
So, you could go to open an older file and find that it’s actually not on your hard drive anymore. That’s where “Files On-Demand” comes in. Those “dehydrated” files can be restored seamlessly when you click on the placeholders. You will need to be connected to the internet, of course. You might not want to rely on the cloud for access to specific files, even if you don’t use them very often. So, there’s an option to flag content for offline access, and Storage Sense won’t remove your local copies.
Flagging offline content isn’t the only tweak available. Microsoft wants you to leave Storage Sense on, so there are various settings to make it less intrusive. Rather than having Storage Sense run daily, you can knock it back to weekly or monthly. You can also edit the amount of time it takes for files to become “-only.” Storage Sense automatically clears out your Downloads folder as well, and you can alter the frequency of this purge.
If the automatic file management isn’t your thing, you can just invoke Storage Sense manually with the “Free up space now” option. Here, you can pick which temporary files and logs will get the ax.
Storage Sense will ask for permission to manage your drive when the new Windows 10 build is live, so you can opt out at that point. Just make sure you know what Storage Sense is going to do before you give it the go-ahead.