How To Clean Up Com Port To Use?

1. Click start → Run → type regedit and click OK button
2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter
3. Now on the right panel, you can see the key ComDB. Right-click it and click modify
4. In value Data section select all and delete reset to Zero (0)
   Its 32 bytes with 8 bits in each byte. A set bit makes a port number (1...256) reserved. 
5. Close Registry editor and then restart your computer. All COM ports are now Free.
   You may need to reinstall any USB-to-serial converter.

How do I clean up COM ports in use?