"Com Port Denied"

#### Issue details
_Please describe the problem, or desired feature_
Tried to connect pixracer to mission planner via bluetooth and a direct connection, but both resulted in a "Com Port Denied" error.
#### Version
_What version was the issue encountered with_
1.3
#### Platform
[ ] All
[ ] AntennaTracker
[ * ] Copter
[ ] Plane
[ ] Rover
[ ] Sub

#### Airframe type
_What type of airframe (flying wing, glider, hex, Y6, octa etc)_
quadcopter
#### Hardware type
_What autopilot hardware was used? (pixhawk, pixracer, PX4FMU etc)_
pixracer
#### Logs
_Please provide a link to any relevant logs that show the issue_

Start by reproducing the "Com Port Denied" error in Mission Planner 1.3 using both Bluetooth and a direct Pixracer connection with the Copter profile. Check whether the issue occurs consistently and capture the relevant logs, then confirm done when either connection works or the failure has a documented, actionable diagnosis.

Written by the indexing model from the issue text.