FAQs

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When using a USB to RS-232 Cable (part MX1130) with a PC running Windows XP, I receive the message "Cannot Connect to Port - All valid communication (comm) ports are in use". How can I resolve this?

Try the following settings for the Blue Napco USB only.

1. Click Start > Settings > Control Panel > System.
2. In the System Properties dialog, click the Hardware tab.
3. Click the Device Manager button.
4. In the Device Manager dialog, open the Ports (COM & LPT) system component.
5. Double-click the USB Serial Port (COM#) to open.
6. Click the Port Settings tab, then click the Advanced button.
7. In the Advanced Settings for COM1 dialog, check the Serial Enumerator and RTS On Close checkboxes.
8. Click OK repeatedly to save and exit.