In order to focus resources on new technologies and operating systems, and to provide users with the most up-to-date and secure experience, beginning January 1, 2022, updates will no longer be provided for the OneDrive desktop application on your personal Windows 7, 8, and 8.1 devices. Personal OneDrive desktop applications running on these operating systems will stop syncing to the cloud on March 1, 2022.
If you are currently using one of these operating systems, we recommend upgrading your operating system to either Windows 10 or Windows 11 to avoid disruption. For machines that do not meet system requirements for Windows 10 or Windows 11 operating system upgrade, you can back up and protect your files by manually uploading them to OneDrive on the web, and continue to access, edit, and share your files on all your devices.
Of note is that if you still use Windows 7 or 8.1 then you'll still be able to manually upload (and download) things to (and from) OneDrive after this date, but you'll have to use a web browser and login that way, using the web interface.
The tie-ins with Windows 10 Mobile, its backup, and its OneDrive client are somewhat unclear, but I'll keep the relevant status page updated each month so that you know what still works and what doesn't, etc.