Bug #9439

Cannot open COM port, access denied

Added by Scott Applegate about 1 month ago. Updated about 1 month ago.

Status:Feedback Start date:10/12/2021
Priority:Normal Due date:
Assignee:- % Done:

0%

Category:-
Target version:chirp-daily
Chirp Version:daily Platform:Windows
Model affected:(All models)

Description

The latest version of CHIRP will not access any COM port to communicate with a radio. The version from 08/30 works fine, the version from 09/30 does not. No change in cable, driver or set up between the two versions. Radio is a UV-5R, cable is a CH340 chipset.

History

Updated by Jim Unroe about 1 month ago

  • Status changed from New to Feedback

Hi Scott,

The problem did not occur due to a CHIRP upgrade. If it did, you could go back to the the "08/30" build and it would work again. I am confident that it would matter.

I have two questions...

1 Did you install the WCH CH340 driver yourself? Windows often fails in its attempt to install this driver. The solution is to download the driver from the chip vendor's website and install it yourself.

2 Are you selecting the correct COM port? CHIRP remembers the last COM port number that was used to clone your radio and re-selects it the next time that CHIRP is opened. If something (Windows assigns a different COM port, a different programming cable is used, etc) would cause the port to change from what it was previously, CHIRP will select the previously used COM port number even if it is no longer available. Check Device Manager to see which COM port number is assigned to your programming cable and then select it in CHIRP.

For example, if I have my CH340 cable plugged in, Windows assigns it COM6. If I swap to my Prolific cable, Windows changes the port assignment to COM3. I will have to manually change CHIRP from COM6 to COM3 or I will get the following message.

       An error has occurred
could not open port COM6: [Error 2] The
system cannot find the file specified.

Also if I plug my Prolific programming cable into a different USB port, Windows will load the driver again and assign a different COM port to the same cable. I will have to use Device Manger to determine which COM port has been assigned to it and select it in CHIRP. Move it to another USB port and another COM port will be assigned. And if I plug the programming cable back into the original USB port, Window will assign COM3 back to it as before.

Jim KC9HI

Updated by Scott Applegate about 1 month ago

Jim,

That is exactly what I did, first I tried reinstalling the current version with no change, then I uninstalled it and installed the 08/30 build which works without issue. I did try removing the auto-installed drivers and installing the ones from that link, again with no change. I am selecting the correct COM port, confirmed with device manager. I also tried different USB ports (and resulting different COM port numbers).

This leads me to believe that the issue lies with the newer CHIRP build, rather than a local configuration issue. I also verified this on another machine as well, the latest build has the same issue while the older one works fine. I have also previously used CHIRP about a month and a half ago, and a year or so ago with correspondingly dated builds, again with no issues until the latest (09/30) build.

Both machines are Windows 10, and I did try running CHIRP as admin as well with no change.

Updated by Jim Unroe about 1 month ago

If it was a CHIRP issue, many people would be having the same issue for the last couple of weeks. So far it is only you.

But just the same I stuck in my CH340 chip based programming cable (I typically use a Prolific chip based programming cable) to make sure. It works fine here with CHIRP 20210930, Windows 10 Pro and CH340 programming cable.

Jim KC9HI

Updated by Scott Applegate about 1 month ago

I'll just chalk it up to some unknowable bug/interaction/config issue then, and stick to the version that works :) I don't have or plan to get any new radios, so the older version is fine anyhow.

Thanks for taking a look at this, I apologize for the waste of time!

Updated by Jim Unroe about 1 month ago

Scott Applegate wrote:

I'll just chalk it up to some unknowable bug/interaction/config issue then, and stick to the version that works :) I don't have or plan to get any new radios, so the older version is fine anyhow.

Thanks for taking a look at this, I apologize for the waste of time!

Did you happen to attempt the 09/30 installation while CHIRP was still running. The installation can update the files that are actively in use and you would have some files updated while others remain at the previous level. Dropping back to the previous version would put them all back to the same version again.

Make sure CHIRP isn't running. Reboot if you have to in order to make sure. Then right-click the latest CHIRP installer and choose "Run as administrator" to perform the upgrade.

Jim KC9HI

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