Welch Allyn Propaq LT v1.60.07 Update Application - Installation Guide - Manual (Page 5)

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Note: Perform step 4 after installation of the update application and before initial use. This allows
the USB drivers to be installed. Subsequent Propaq LTs may then be connected with or without the
application running.
4. Before the Update Application starts, power-on and connect a Propaq LT per steps 1-4 in Section 3.

In Windows 7, the USB drivers should install without prompting.

In Windows XP, the New Hardware Wizard will ask if Windows Update can search for software.
Choose “No, not this time.” Then choose “Install the software automatically.”