This is very annoying. I booted up Vista the other day to find that my Volume and Network icons had simply vanished. No reason for this whatsoever. So off I toddled to the control panel to add them back in and guess what? I couldn’t! For some reason, I could not find the ‘put volume control in system tray’ tickbox or the Network equivalent either.
Then I tried going and right-clicking the start button and selecting properties and going to the ‘Notification Area’ tab to enable them there. But they were greyed out and unselectable!
Oh what a joy. I finally found the solution - its not very elegant I’m afraid but if you have the same problem then open up regedit (Start -> run -> regedit) and then navigate to:
HKEY_CURRENT_USERSoftwareClassesLocal SettingsSoftwareMicrosoftWindowsCurrentVersionTrayNotify
Right-click ‘trayNotify’ and select delete. This should clear the registry settings for it. Now, you need to re-start the explorer shell. A reboot or log-off/log-on is the most simple way to do this. Then right-click the start button -> properties -> notification area tab and hopefully now you can select the volume and network icons!