If your mouse stops working after your system has been inactive or wakes up from sleep, try modifying your Bluetooth adapter's power settings.
Launch Control Panel > System and Security > System > Device Manager.
Under Bluetooth Radios, right-click your Bluetooth adapter (ex. Dell Wireless 370 adapter), and click Properties.
In the Properties window, select the "Power Management" tab, and clear this check box: "Allow the computer to turn off this device to save power".
Click OK and then reboot the PC.
If this solution doesn't work, restart your computer and try again.
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