Files On-Demand and Sync Advantages across a team

Iron Contributor

In the Office Blog article, there is this paragraph:


In addition to users, Files On-Demand benefits organizations and IT admins. Today, when someone syncs a SharePoint Online team site, files are re-downloaded on all synced devices when anyone makes a change. Files On-Demand will reduce network bandwidth by eliminating the need to continuously sync shared files on every synced device as teams collaborate.


Does this mean that when a file is opened, it's state will be checked against the server and if the server is modified (newer), then the file will be on-demand downloaded for use?

In effect, the user will never see an out of synch file if they remain on-line? 



Owen Allen



6 Replies

My understanding is that Files On Demand are not synced by default. They are synced only if the user chooses to keep them locally. Otherwise, only "stubs" (well, sort of...) will be visible locally. The files will be downloaded locally only when actually opened (i.e. on demand).

Hence, since such files are not kept locally, by default, there is no need to redownload them on every change (and so some bandwidth is saved).

Just my two cents...

Hi Salvatore,

it sounds liek we are saying the same thing - when a user is on-line, and the Files are On-Demand, (and "Always Keep on this device" is NOT set), there will not be incremental synching or updating of the file, but the current version of the file will be downloaded when the user moves to open the file.  


Here are two more scenarios and my assumptions. Can you clarify if your understanding is different?


When the user closes the file, (still in the situation where "Always Keep On This device" is NOT set), the file will remain on the user's client device, in full (not in a stub), in the same version as when it was saved, regardless of how many times the server version is updated, until the user moves to open the file anew. At that time, OneDrive will compare the local file against the server version and download the server version, replacing the file on the client device in a seamless way, so the user always feels that he/she is opening the most recent version.


Now, let's take the scenario where "Always Keep On This Device" is set for a file. In this case, I assume that the OneDrive synchronization that we've always enjoyed remains in place - that the file will be updated with every update to the server copy. 


Looking forward to being able to see this as it ships.




Hi Owen.

I believe that in both your scenarios the local file (resulting from the on demand download in the first case, or locally persistent in the second case) will sync regularly. In other words, once downloaded, the file is a regularly synced file in both cases. The only difference between the two scenarios is that in the first scenario the local copy can be deleted by the system if needed.

Of course I could be wrong: we will see...


@Owen Allen

It looks like it works as I supposed...

"If you double-click a file that is marked “Available when online” it will automatically download so you can open it, and it will always be available offline after that. You can, of course, later right-click it and choose “Free up space” if you would prefer it to stay offline-only." from


Awesome. Looking forward to seeing it in my version of the client. I'm still at 17.3.6816.0313. Are you seeing it in your builds yet, or do you know when we should expect it? 

Unfortunately, a simple NGSC update will not make the trick...

OneDrive Files on Demand will be released publicly in the Windows 10 Fall Creators Update.