If you are having problems getting your updater to recognize the MS-500/600 when plugging it in, 
login as ADMIN or have your IT Team perform the following steps:

Unzip 'AmplifierFirmwareUpdater.zip' to desktop

Plug in MS500 or MS600 to USB

Open Device Manager (Click START, type 'device', click on device manager under 'Best Match')

Locate 'CA300 Audio Mixer' device and double click (Likely in Other Deivces with Yellow Error icon)

Click Update Driver

Browse My Computer for drivers

Browse to USB Drive / AmplifierFirmwareUpdater / Firmware Updater / Driver (NOT ANY SUB FOLDERS IN THE DRIVER FOLDER)

Next (You should see green status bar installing files, then Windows Successfully updated your drivers

Close out updater and device manager

UNPLUG Amplifier from USB DEVICE

Run MSGL-Main_Updater 

Press Control + Alt + P + A to open advanced tabs

Go to settings CHECK the following boxes:
 Allow Re-updating
 Audible up-to-date indication
 Bulk / Auto-update Mode
 
Click Firmware TAB

Unplug and plug back in Amplifier (It will say "Updated" when complete!)

