Bluetooth device doesn’t work after computer wakes from sleep mode

Perform the following steps if you bluetooth device doesn't work after computer wakes from from sleep mode:

Windows

1. In the Device Manager, change the Bluetooth wireless adapter power settings: 
   • Go to Control Panel > System and Security > System > Device Manager 
2. In Device Manager, expand Bluetooth Radios, right-click on the Bluetooth wireless adapter (ex. Dell Wireless 370 adapter), and then click Properties.
3. In the Properties window, click the Power Management tab and uncheck Allow the computer to turn off this device to save power. 
4. Click OK.
5. Restart your computer to apply the change.

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Macintosh 

1. Navigate to the Bluetooth preference pane in System Preferences: 
   • Go to Apple Menu > System Preferences > Bluetooth
2. In the bottom-right corner of the Bluetooth preference window, click Advanced.
3. Make sure all three options are checked: 
   • Open Bluetooth Setup Assistant at startup if no keyboard is detected 
   • Open Bluetooth Setup Assistant at startup if no mouse or trackpad is detected 
   • Allow Bluetooth devices to wake this computer 

     

     NOTE: These options ensure that Bluetooth-enabled devices can wake your Mac, and that the OS X Bluetooth Setup Assistant will launch if a Bluetooth keyboard, mouse or trackpad is not detected as connected to your Mac.
4. Click OK.