OneDrive deleted local files and started syncing old files !

I share your concern. I use OneDrive as a place to manual backups and some bulky stuff I'd just prefer to keep securely in the cloud.

I think that Microsoft want, expect, and therefore really try to FORCE, all users to use OneDrive as their working data source for everything. Whilst this may be a great way to work if you have a 10Gbps internet pipe, most mortals like us have to make do with download speeds of around 8Mbps to 80Mbps with upload speeds only about a sixth of that. 

When OneDrive do a major update, I suspect that staff are think it's safe to assume that the OneDrive data is the the most up-to-date and that users don't really use their hard drives for anything.

They make the same kind of assumptions such as C:<user>documents will always be the location of the Documents folder, even when you have an SSD with only enough room for Windows. (In my case, my C drive suddenly began to run out of space when I decided set some OneDrive folders to "local". At that point, I hadn't realised that OneDrive had taken it upon themselves to delete my D-drive data and change the system users folders to the C drive.

I wish Microsoft would come clean and admit they've made a mistake that has affected lots of their customers. I've fixed my setup now, but, unless OneDrive staff recognise their error, will it happen again?

Happened to me. After enabling OneDrive auto backup/sync all my local files have been deleted and uploaded to OneDrive. Facepalm microsoft, if this is expected result when doing this action, atleast MAKE IT SUPER OBVIOUS TO THE USER THAT THIS IT WILL HAPPEN!!!

I was fortunate to have almost all my data in OneDrive cloud, albeit with thousands of duplicates. (I wonder who had the bright idea of adding suffix " - Copy"? It's a term you can't search for even if you use file: so the dups have to be hand zapped.)

I agree very much re their deletion of our data. If anyone else was caught deleting data from a machine, they'd be arrested!

Microsoft seem to insist that you go straight to the cloud for working files. That's okay if you work for Microsoft and a dirty great data pipe, but many mere mortals have slower data speeds. I hate it that you can't exclude the OneDrive folder from windows seearches. If I type in the name of a file in my local drive, it always suggests the copy on OneDrive. It's very annoying. 

My message is .. stay calm! It's not worth the ulcer. (I know, I've had them.)

Thanks for replying. Unfortunately, the only things in recycling were the few duplicates I'd noticed before I realised the scale of the problem. The main user system folders like Documents, Pictures, Desktop have just vanished and turned up in OneDrive. All the shortcuts to locations like D:user/documents have been magically changed to point to their new OneDrive locations. 

It feels as if Microsoft have decided that I'm going to base my active files on the cloud whether I like it or not.

I've got a support contract so I'm going to get them to sort it out. I've spent days checking I've only got one of everything. 

Let's hope Microsoft don't just reset it again!

I was able to find them!  BUT there are a lot of duplicates with various dates!!!