Hey guys, I recently had to replace the hard drive in my computer and I've gone back to set up APM and MP. I followed the wiki as I did the first time I downloaded MP and everything worked fine. Now, after following the wiki, I keep getting "COM Port 4 does not exist" when I try to connect the APM board.   I went to Device manager and it seems that it is assigned to Com "Port 2, Hub 4" however, when I pull the drop down box in MP it gives me "Com Port 4 Ardu Mega" as the option. Any ideas on how to fix this. I have the latest drivers installed and the most updated MP.

MP Error.jpg

Device Manager APM.jpg

Drop Down.jpg

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  • 1.2.20 has a driver bug.  I got it fixed by downgrading to 1.2.19 and then going to C:\Program Files\APM Planner\Drivers and running the appropriate "bit" application which installed the drivers and it works now.

  • Also, I attached some screen shots. MP Error is when I click on the Firmware Ardu Plane. Device Manager APM is a screen shot of my device manager. (Note no com port assigned next to Ardino Mega and in the properties window, location is Com 2 Hub 4). The Drop Down show the options for com ports in MP.
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