This article explains why the Windows NT v3.1c driver always show device on COM1 even though it's on COM2

The below describes issue with incorrect COM Port indicated in the Windows NT v3.1c driver.

NOTE: Windows NT is no longer supported by Microsoft or Elo Touch Solutions.

Incorrect COM Port Indication

The port of the touchscreen is always indicated as COM1, even if the connection is to another port. This is a bug in the driver code which was not corrected during the era of NT support.