Hi Mithun,
Thank you for posting your query in Microsoft community.
Based on the issue description, I understand that when you tried to change the Bluetooth Support Service logon user to NT AUTHORITY\LocalService with blank password it revert back with filled password fields.
First, I would also suggest you to start the Bluetooth service and set it to Automatic:
a. Go to the Start screen.
b. Type “Services.msc” without quotes and press Enter.
c. Right click on Bluetooth support service and click on Properties.
d. Set the Startup type as Automatic and then click Start under Service status.
e. Click on OK.
If the issue persists, try updating the device’s driver:
- Check Windows Update for driver updates..
a. Swipe in from the right to bring up the charms, and select Settings.
b. Tap or click Change PC Settings.
c. Select Update and recovery, then select Windows Update.
d. Select Check for updates. Make sure to look at the Optional updates in the results.
2. Check the device manufacturer’s site for updated drivers.
3. Check the radio manufacturer’s site for updates. To determine what make and model of Bluetooth radio you have:
a. Swipe in from the right to bring up the charms and select Search, and search for device manager. Open Device Manager from the search results.
b. In Device Manager, expand Bluetooth, and look for a device with a name starting with Broadcom, Intel, or Qualcomm Atheros (these are the major radio manufacturers). Check the website of your radio manufacturer for driver updates.
c. If you don’t see one of these manufacturers, but instead see Generic Bluetooth Adapter:
i. Press-and-hold or right-click on Generic Bluetooth Adapter, and select Properties
ii. Select the Advanced tab.
iii. Note the number next to Manufacturer ID.
iv. Find that manufacturer ID on this page: https://www.bluetooth.org/en-us/specification/assigned-numbers/company-identifiers (Common ones will be 2 = Intel, 15 = Broadcom, 69 = Atheros)
4. Once you have updated your Bluetooth drivers, please try using your device again. In many cases, updating to the latest drivers will resolve the issue. In some instances, you may need to un-pair and re-pair the device from the Bluetooth settings (from
the Settings charm, select Change PC Settings, and then select Bluetooth) to completely fix the issue.
Hope this information helps, please reply with the status of the issue for further assistance.