To begin with, the headset will need to be charged long enough so that it will power on as it would when it’s functioning normally.
You will need to run the Sena Device Manager again. After selecting the headset from the list of selectable devices, press Next. In the following menu where it tells you to "Power off the headset and connect to PC with the USB cable. LED turns on red." plug in the headset as instructed. At this point, perform a "Fault Reset" on the headset. Refer to the headset's User's Guide on how to perform a "Fault Reset". The red LED on the headset will not change. Now you should be able to power on the headset. If the headset does not power on then that is perfectly normal. If your speakers are loud enough then you will hear the sound of a USB device being connected once you have press and performed what is necessary to power on the headset. Then press Next on the menu and you should get a pop-up menu saying that the current firmware is v(current version) and would you like to update to newest. Say Yes and the firmware should update as normal allowing the headset to return back to functioning again once the update process is done.
If the case where the driver for the headset was not installed correctly then use the follwing steps below.
Uninstall the Sena Device Manager and redownload the Sena Device Manager for your operating system's version. Before beginning the installation process, right-click on the installation file and choose "Run as Adminstrator". Once installng make sure after plugging in the name of the headset when it asks you to that you see the "Welcome to the Device Driver Installation Wizard" so that the driver for the SMH10 is correctly installed. If you do not see that and are running a Windows machine, then please go the Windows Device Manager (Start > Control Panel > Device Manager) and you should see the headset listed once the unit is powered. If the headset is listed under "Other Devices" or "Universal Serial Bus controllers", then right-click it and choose Update Driver Software. Then choose Browse my computer for driver software. Click the Browse... button and select C: > Program Files > Sena Technologies then click OK. The "Welcome to the Device Driver Installation Wizard" should appear now and install the driver for the headset. Now you can use the Sena Device Manager to update the firmware on your headset.
If the above does not work then please go to the menu, of Sena Bluetooth Device Manager program, by moving to Start Menu -> All Programs -> Sena Technologies -> SenaBluetoothDeviceManager then select "Install Driver" in the SenaBluetoothDeviceManager menu to begin the "Welcome to the Device Driver Installation Wizard".