Hope these steps can resolve this:
- Check the OneDrive sync settings on your desktop to ensure that it's set up to sync the folders where your large file is located. You can find the sync settings in the OneDrive Activity Center, which can be accessed by clicking the OneDrive cloud icon in your system tray.
- Ensure that there is enough storage space on your local device for the large file. If your device doesn't have enough space, the file won't sync.
- Use the OneDrive desktop client for uploading very large files, as it's recommended for better performance. Microsoft has increased the file size limit from 15GB to 100GB, so your large file should be supported.
- If the file has disappeared, it could be due to a sync issue. Check the OneDrive recycle bin online to see if the file is there. If you find it, you can restore it from there.
- If the zip file didn't work, it might have been corrupted during the download. Try downloading the file again directly from the OneDrive online interface, rather than as a zip file, if possible.
- If you continue to face issues, you may need to check for any sync problems on your OneDrive desktop client.
Remember, any changes you make to files in your OneDrive folder on your computer will sync automatically when you're back online.