What happens when you delete files in the cloud - Microsoft Support
Training: We'll show you what happens when you delete a file or folder on OneDrive with one device what happens on your other devices.
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If you delete from OneDrive, they'll no longer be available on any PC/Phone that is connected to your one drive account. However, if your files are copied out of the OneDrive folder to another folder on your machine, you can make a "local" backup to be sure they won't disappear.
If you're worried about losing files stored in OneDrive, there are a few manual methods you can try to recover them. First, check the OneDrive Recycle Bin; deleted files are typically stored there for 30 days before being permanently removed. You can access it by signing in to OneDrive and clicking on the "Recycle Bin" option in the left sidebar. If the files are not there, you can also check the "Version History" feature for any previous versions of your documents.
If these methods don't work, you might consider using a professional data recovery tool like the BLR Data Recovery Tool. This software is designed to recover lost or deleted files from various storage devices, including OneDrive. With its advanced scanning algorithms, it can help you retrieve files that may have been accidentally deleted or lost due to sync issues. The tool also offers a free preview option, allowing you to view recoverable files before proceeding with the restoration, making the process more efficient and reliable.