How to delete serial number in win7

Delete redundant serial numbers, as follows:

1. In Windows system, press Start >; Execute > enter cmd and press enter.

2. After the command character window appears, enter

set dev mgr _ SHOW _ non present _ DEVICES = 1

Press enter.

Development management

Press enter.

3. then click > view > show hidden devices. now you can delete redundant ports. Please be sure to restart after deletion.

4. Reinstall the Bluetooth management software

5. Open the registry HKEY _ local _ machine/system/current control settings/control /comname arbitration.

Delete ComDB and try again! (Note: This will rebuild all COM ports). If not, restart the computer!