The device connected to a UPort COM port or a multi-port card is identified as PnP serial mouse and a cursor jumps around the screen.

This problem can be misinterpreted as a problem with a multi-port card or a driver from MOXA, however, it is caused by Microsoft Windows 2000 / XP / 2003 / 7 OS.

This problem can be misinterpreted as a problem with a multi-port card or a driver from MOXA, however, it is caused by Microsoft Windows 2000 / XP / 2003 / 7 OS.

The problem lies within Plug&Play function in Windows. When Windows is booting, the OS tries to identify new devices my requesting each communication interface, including COM ports. If there is data transmission ongoing via a COM port, Windows OS will mistake it for a response to its request and compare it to the system register and the device manager.

It will identify the serial device as a new device. As a rule, Windows will take it for a serial mouse and it will interfere with the original mouse. Such behaviour is typical for any version of Microsoft Windows.

Solution:

1. Switch off the serial device until Windows OS is completely booted.
2. Refer to Microsoft Knowledge Base: https://support.microsoft.com/en-us/kb/283063
3. Microsoft also provides the COMDisable utility tool. To find out more, visit Microsoft Knowledge Base: https://support.microsoft.com/en-us/kb/819036