Microsoft suddenly disabled OneDrive support for non-NTFS disks this week, wreaking havoc for users with FAT32-based removable drives. But here’s the kicker: This should have never worked.

“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,” a Microsoft statement explains. “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.”

Image courtesy of Neowin

What’s not clear, of course, is when this support was supposed to have ended. And that users have been utilizing FAT32-based microSD cards and other removable storage with OneDrive for years. The problem impacts drives formatted with exFAT and ReFS as well, Neowin reports.

The issue is that Microsoft just suddenly pulled the switch without warning anyone. And for those who had been using this functionality, its sudden disappearance—the error message above is seen after a reboot—is most unwelcome.