ActionTec SBT100U User Manual page 23

Follow the procedure below to update the Receiver's firmware and the
ScreenBeam Wireless Display software:
1. Make sure that ScreenBeam Wireless Display software is
disconnected from the Receiver. Then, right-click a Receiver's profile
from the ScreenBeam Wireless Display window and select Check for
updates....
Note: Performing a software update may cause the ScreenBeam Wireless
Display application to restart. If this occurs, relaunch the ScreenBeam
Wireless Display application after the update is completed.
ScreenBeam USB Transmitter
23