Cause
If the following error message appears when you try to start the Pass-Through Configuration Tool, the virtual COM port driver may not have been installed.
Solution
Make sure that two or more COM ports have been registered.
Select [Device Manager] from the [Control Panel] of your computer.
Make sure that two or more COM ports have been registered in [Ports (COM & LPT)].
When [Device Manager] does not display any COM ports for [Pass-Through for User]
Select [Show hidden devices] from the [View] menu to display all COM ports.
When [Device Manager] displays a different number of COM ports for [Pass-Through for AGP] and [Pass-Through for User] (example, two and three ports)
Uninstall the [Pass-Through Configuration Tool] and the virtual COM driver.
To uninstall the virtual COM port driver, be sure to refer to the following Pass-Through Configuration Tool guide to understand the procedure completely.
[Pass-Through Configuration Tool] installation
Device/PLC Connection Manual, Pass-through Function Guide 2 Installation
[Pass-Through Configuration Tool] uninstallation
Device/PLC Connection Manual, Pass-through Function Guide 5, Appendix 5.1 Uninstallation of Virtual COM Pass Driver/Virtual COM Port Driver