Microsoft disables OneDrive thumbnails

[German]Microsoft has now also started to reduce the data traffic associated with the OneDrive online storage. Since a few days no preview images are displayed on macOS and Windows for several file types on synchronized local OneDrive files.

In view of the sharp increase in Internet traffic in the wake of the coronavirus crisis, Microsoft is now also reducing the amount of data traffic generated by OneDrive. I haven't noticed it myself because I'm not using it – and I still see thumbnails in my browser on the OneDrive online storage device.

The OneDrive Client allows the placeholder function Files on Demand to be activated in its properties. This causes the client to then store thumbnails from OneDrive in a local folder on the client. This should not take up any space for the actual files on the client. This can be seen in the following properties window.

The information is stored in streams in the NTFS file system. Only when a file is downloaded to the client for editing does a file transfer occur. In the past, Microsoft had downloaded at least one preview file for files stored on OneDrive and synchronized with the OneDrive client.

Now Martin Geuß reports at Dr. Windows about restrictions in Windows Explorer as well as in the Mac Finder. According to his statement, certain file types have not been displaying thumbnails in the Medium Icons and Extra Large Icons display modes for several days.

In the above screenshot, the Word files in Explorer window do not have thumbnails – the image file, however, is saved locally. According to Martin, graphics files are not affected, but the preview of PDF documents and video files is no longer displayed. Just as a hint, in case this happens to someone and he suspects the error to be his own.

Martin's statement is that Microsoft Business customers have informed Office 365 Admin Center about this temporary restriction. But consumers are also affected by this measure with their OneDrive.

Addendum: German blog reader Andreas P. pointed me to this ZDNet article where Mary Foley had the same details. There you can find the confirmation that PDF and video files are no longer previewed. Thumbnails of photo files (like JPEG, JPG, PNG etc.) are not affected by this change.

In March 2020, Microsoft also described in this article the temporary measures towards content migration, data loss prevention (DLP) and backup solutions. Many SharePoint Online and OneDrive customers run business-critical applications in the background. These include content migration, data loss prevention (DLP), applications that scan the service, and backup solutions. To remain highly available, Microsoft is moving some operations to regional evening and weekend hours.