Follow the procedure given below:

1. Open the Device Manager on your host computer/PC.
2. Connect the UPort to the host computer (host).
3. In the Device Manager, expand the Universal Serial Bus Controllers tree. You will see your native COM port listed as Communications Port (COM1).
4. Right-click on Communications Port (COM1) and select Properties.
5. In the Properties window, click on the Port Configuration tab and then click on Port Setting.
6. For the Port Number field, use the pull-down menu to select COM2 for your Native COM Port and click OK.
7. Click on the OK button in the Properties window. In the Device Manager, the native COM port number should change to COM2.
8. Connect your UPort 1100 Series to your host.
9. Open the Device Manager on your host and check the Ports (COM & LPT) option. The Moxa USB Serial Port for your UPort should be set to COM1.
10. If the Moxa USB Serial Port for your UPort is not set to COM1, follow the procedure detailed in steps 1 to 7 above to change it to COM1.