Based on the information provided in the context, if Bluetooth is not working or missing after an upgrade to Windows 10, users may need to check their hardware manufacturer's or OEM's website to install Windows 10 compatible drivers. However, if Bluetooth is not turning on after a recent Windows update, there are a few steps that can be taken to try and resolve the issue. One possible solution is to try restarting the PC and then attempting to turn on Bluetooth again. If that does not work, users can try updating their Bluetooth drivers by checking Windows Update for a more current driver. If that still does not work, users can try uninstalling and reinstalling their Bluetooth drivers. If none of these steps work, users can file feedback in the Feedback Hub with details of what is happening.
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