I'm still using MX-850 editor. It is in a folder labeled "Program Files (x86)" within Windows 10. I'm using Parallels 16 on an intel Mac running Catalina (OS 10) which is the last OS version this computer will run. I think the (x86) means the apps within are 32-bit. When I upgrade to an M2 Mac, Parallels 18 and Windows 11, will the MX-850 app still run and upload/download to my 850's?

Ok, I've updated to Windows 11 Pro. The MX-850 app does work. However, the keyspan adapter can not be found. In Device Manager, it shows up under Other Devices. When checking Properties it says there are no compatible drivers for this device. It also says that drivers for this device are not installed. I downloaded the driver file from Tripp-Lite for the adapter and followed the instructions as follows without success. It did say the driver installed properly but it still won't see the adapter nor do the drivers show up when I go back to the adapter in Device Manager. Any suggestions?

Directions from Tripp-Lite:
Windows 11 Pro

1. Do not initially attach the device.
2. Download the correct driver from the product's support page on www.tripplite.eaton.com and unzip the driver into a folder of your choice.
3. Locate and open the Device Manager program from your computer's system tools.
4. Using the menu at the top, choose "Actions | Add drivers".
5. Browse to the folder where the driver is located, OK the installation.
6. Connect the device to your computer's USB-A port using the included cable.
7. Open Device Manager.  The device should be correctly identified and have a driver available.

When downloading the most recent driver for this product it is important that the previous driver be manually uninstalled and removed from the computer. If the old driver is not removed the Device Manager will still attempt to utilize the old driver despite the presence of the new driver.

Well, I have found out that one must obtain an ARM driver for the chipset used in your cable or external device. I've contacted keyspan to see if they have a driver and they do not at this time but was going to check with engineering to determine if one is being worked on for Windows 11 Pro ARM. They are supposed to get back to me. We will see how that goes.

In the meantime, I found out that there are ARM drivers for adapters that have an FTDI chip.  I ordered a Gearmo USA-FTDI-A36 ( [Link: gearmo.com]) from Amazon ( [Link: amazon.com] ).
After getting the new adapter, follow the instructions I posted below. Hope this helps someone.

To get drivers for USB to Serial Adapter for Windows 11 Pro with ARM

You must purchase a USB to Serial Adapter that has the FTDI chip.
Be sure the USB to Serial adapter is connected to Windows by clicking on Devices in the menu above Windows and selecting “USB & Bluetooth”, then select the USB to Serial adapter if not already chosen.

Navigate to [Link: ftdichip.com]
Scroll down to Processor Architecture.
Download the latest for Windows Desktop under the heading of ARM
I downloaded 2.12.36.4A****
In the Comments column for the Windows Desktop row, open the link to Installation Guides.  (Copy of the appropriate section of the guide is below).

I copied the file 2.12.36.4A**** to my Windows desktop.

NOTE:  After driver is completely installed and all instructions followed, reopen Device Manager.  Look for Ports (Com & LPT).  Right click and choose Properties.  Click on the Port Settings tab.  Then click Advanced.  Change Latency Timer (msec) to 1 (Default is 16).  Click OK, then in the USB Serial Port (COM3) Properties window, click OK.  Then close Device Manager.  Restart Windows.

Afterwards, the USB to Serial adapter worked.

Here are the instructions which must be followed all the way to the end.
3.3 Manual Installation 
If no suitable driver is automatically found, then the following procedure should be followed.
Note: This is the only method to install the ARM64 or universal versions of the driver.
Firstly, download the latest FTDI windows driver files from [Link: ftdichip.com] and save the driver .zip file to a known folder on the PC. The desktop can be used so that the driver folder can be easily located then extract the .zip file.
To locate the device manager on windows 10/11, right click on the Microsoft logo at the bottom left-hand corner of the screen and select Device Manager as shown in Figure 3.9.
Figure 3.9 Device Manager Access 
In the Device Manager window there should be a device under Other Devices with a yellow warning symbol to indicate a problem i.e. no driver installed, as shown in Figure 3.10. The text next to this device will depend on the device attached. In this example the device was a USB Serial Cable.

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Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
Figure 3.10 Device Manager View 
Right click on the other device (USB Serial Cable in this example) to bring up a menu as shown in Figure 3.11. From the displayed menu select “Update Driver Software...”
Figure 3.11 Update Driver Software 
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Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
This then displays the option for an automatic search or a manual search. Select the second option to browse manually as shown in Figure 3.12.
Figure 3.12 Browse my computer for Driver Software 
In the address box put the exact location where the drivers have been saved to. The location should be the top-level folder of the extracted files and contain two *.INF files. It is not necessarily the exact same location as shown in Figure 3.13. The drivers could have been saved anywhere on the PC by the user.
Figure 3.13 Search Location 
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Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
After entering or browsing for the address, select “Next” to start the installation as shown in Figure 3.14.
Figure 3.14 Installing driver software 
When the installation has finished a completion screen is displayed as shown in Figure 3.15.
Figure 3.15 Successful Driver Software Update 
Press Close to close this window and go back to the Device Manager Window.
If the Virtual Com Port option has been enabled to load then Device Manager will show a device under Other Devices but in addition to this there is a new entry under Universal Serial Bus

11 Document Feedback Copyright © Future Technology Devices International Limited
Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
Controllers indicated in Figure 3.16 as the USB Serial Converter. This indicates the bus layer of the driver is installed. Installing the Virtual Com Port layer of the driver is a repeat of the last few steps.
Figure 3.16 Device Manager View 
Right click on the other device (USB Serial Cable in this example) to bring up a menu as shown in Figure 3.17. From the displayed menu select “Update Driver Software...”
Figure 3.17 Update Driver Software 
This then displays the option for an automatic search, or a manual search as shown in Figure 3.18. Select the second option to browse manually

12 Document Feedback Copyright © Future Technology Devices International Limited
Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
Figure 3.18 Browse my computer for Driver Software 
In the address box put the exact location where the drivers have been saved to. The location should be the top-level folder of the extracted files and contain two *.INF files. It is not necessarily the exact same location as shown in Figure 3.19. The drivers could have been saved anywhere on the PC by the user.
Figure 3.19 Search Location 
After entering the address select “Next” to start the installation as shown in Figure 3.20.

13 Document Feedback Copyright © Future Technology Devices International Limited
Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
Figure 3.20 Installing driver software 
When the installation is finished a completion screen is displayed as shown in Figure 3.21.
Figure 3.21 Successful Driver Software Update 
Note this screen also displays the COM port number assigned to the device.

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Application Note
AN_396 FTDI Drivers Installation Guide for Windows 10/11 
Version 1.1 Document Reference No.: FT_001281 Clearance No.: FTDI#486
Press Close to close this window and go back to the Device Manager Window as shown in Figure 3.22.

Figure 3.22 Device Manager View 
This time Device Manager does not have an entry under Other Devices but does show entries under Universal Serial Bus Controllers and Ports (COM & LPT). Figure 3.22 displays a correct installation. The device is now ready to use on COM3.
Note: Not all devices will install to COM3. The COM port allocation is determined by the installation wizard based on the next free com port as designated in the PC registry. The COM port can be reassigned to another free port in advance properties as shown in Figure 3.23. FTDI have also produced a utility called COM PORT Assignment which can help assign the port to a different COM port number.


Figure 3.23 Advanced Settings 

If users have the Keyspan USA-19HS USB to Serial adapter and want to be notified if/when a driver becomes available, you can sign up here:

[Link: tripplite.eaton.com]