Over the past few days, a number of OneDrive users have been asking about a seeming change in how the cloud storage system saves files.

As users on Reddit and Microsoft support forums have noted, OneDrive files cannot be saved to anything other than disks formatted for the NTFS file system. This especially has affected users who had been using SD cards to save files somewhere other than on their storage-limited laptops.

Users attempting to link their OneDrives to anything other than an NTFS-formatted drive get a message saying their OneDrive folders cannot be created in the locations selected.

When I asked Microsoft officials why they had made this change, I received the following (odd) statement from a spokesperson:

“Microsoft OneDrive wants to ensure users have the best possible sync experience on Windows, which is why OneDrive maintains the industry standard of support for NTFS. Microsoft discovered a warning message that should have existed was missing when a user attempted to store their OneDrive folder on a non-NTFS filesystem – which was immediately remedied. Nothing has changed in terms of official support and all OneDrive folders will continue to need to be located on a drive with the NTFS filesystem.”

I also asked why Microsoft “remedied” this situation without first warning users about the change. So far, no word back on that one.

Some are speculating,as OnMSFT.com notes, that Microsoft may have made this OneDrive change was/is somehow related to the coming new OneDrive Files On-Demand feature, i.e., the replacement for OneDrive Placeholders. I also asked Microsoft this and still have not heard back.

Update: A Microsoft spokesperson said the change was unrelated to OneDrive Files On-Demand. The company had no comment on my other question about why the NTFS change happened with no warning.

As ArsTechnica notes, older file systems, such as FAT32 and eFAT, and even newer ones like ReFS, also are not supported now because of the NTFS requirement.