We are developing a desktop application under Windows 10 x64 v2004 to control virtual USB COM ports where the devices will be connected/disconnected several times during operation:
- While connecting to a virtual COM port, we get sporadic access denied errors due to more than one virtual COM port being assigned the same port number
- Device Manager shows two USB serial devices with the same COM port number:
- Properties of the two USB serial devices simultaneously assigned the same
This leads me to believe this is a bug in the OS:
- What is the reason that one device is listed as USB Serial Port, while the other is listed as USB Serial Device?
- Is one of the two driver manufacturers not following Microsoft's device driver rules?
- Can that difference explain the root cause of this issue or is there still a general issue in the virtual port addressing?
To automatically correct this, is it possible to cause the OS to re-assign the port number of an affected virtual COM port?
- In a case like this, the only thing I can currently do is the lousy workaround of asking the user to unplug/plug back in the second connected device