Virtual COM port issues

I'm running the latest version of Windows 11 ARM64 under the latest version of Parallels Desktop Pro on an Apple Macbook Pro M1 Max. I have 16 of RS232-to-USB virtual serial ports connected to USB docs that are connected to the Mac. Some are connected via single RS232-to-USB serial converters and 8 of them are connected via an 8-port RS232-to-USB serial converter. All the converters use FTDI chips. All of the ports are configured to automatically connect to Windows not the Mac. Everything works well, except for two issues:

1. When I reboot the virtual machine, some of the ports get reconnected to Windows, but others do not. I believe the difference is that the ports using single-port RS232-to-USB converters do get reconnected to Windows, but the ports using multiport RS232-to-USB converters do not (e.g., the 8-port converter and a couple of devices that appear as dual COM ports.) When I pull down the Devices->USB menu, some of the ports are checked and others are not. Once i check the unchecked ports, they're connected and all is well until the next time I reboot. Note that if I go into USB configuration, the ports that aren't checked are correctly designated to automatically connect to Windows, even though they don't.

2. If I exceed a certain number of virtual COM ports (not sure about the exact number) I get a message that there aren't enough virtual ports to be able support another one. I don't see why there should be any limit, but if there must be, could you raise it to at least 32 and preferrably 64?

Thanks.
 
I'm running the latest version of Windows 11 ARM64 under the latest version of Parallels Desktop Pro on an Apple Macbook Pro M1 Max. I have 16 of RS232-to-USB virtual serial ports connected to USB docs that are connected to the Mac. Some are connected via single RS232-to-USB serial converters and 8 of them are connected via an 8-port RS232-to-USB serial converter. All the converters use FTDI chips. All of the ports are configured to automatically connect to Windows not the Mac. Everything works well, except for two issues:

1. When I reboot the virtual machine, some of the ports get reconnected to Windows, but others do not. I believe the difference is that the ports using single-port RS232-to-USB converters do get reconnected to Windows, but the ports using multiport RS232-to-USB converters do not (e.g., the 8-port converter and a couple of devices that appear as dual COM ports.) When I pull down the Devices->USB menu, some of the ports are checked and others are not. Once i check the unchecked ports, they're connected and all is well until the next time I reboot. Note that if I go into USB configuration, the ports that aren't checked are correctly designated to automatically connect to Windows, even though they don't.

2. If I exceed a certain number of virtual COM ports (not sure about the exact number) I get a message that there aren't enough virtual ports to be able support another one. I don't see why there should be any limit, but if there must be, could you raise it to at least 32 and preferrably 64?

Thanks.

Hello @RichardG17 ,

Thank you for reaching out.

We have created a ticket to assist you with these issues and will contact you at v*****y@m*****x.org with further updates.

Best regards.
 
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