I've searched, read, followed instructions from, many articles about editing the registry for Icon Streams, stopping Explorer, restarting Explorer, logging off, rebooting, etc., and nothing fixes this problem.
When I reboot my computer, the Volume, Network and Power icons in the system tray are gone. I can start/stop Explorer which does fix the problem until I reboot. I don't think I should need to do this each time I boot my computer...
I'm a very computer literate user, so I feel I know what I'm doing. This one has me baffled.