The HTC Sync Manager Serial Interface Windows driver is a piece of software that allows your HTC smartphone or tablet to communicate with your Windows PC over a USB connection, typically for data synchronization and management tasks. The driver enables features like syncing contacts, calendars, photos, music, videos, and other content between your HTC device and your computer. It is often required when using HTC Sync Manager, which is a utility tool designed to help manage your HTC device from a PC.

In addition to syncing data, the Serial Interface part of the driver may also enable other functions like USB debugging (used for development and troubleshooting), as well as transferring files, updating firmware, or using your device for tethering.