I'm a Vista user. I don't remember at what point exactly, but suddenly the network icon in the notification area disappeared. When I went to the taskbar properties, under the notification tab, the check-box for the Network & Volume was greyed out. When I did some research, I found that this is a common issue with many Vista users & Microsoft will probably release a patch or service pack addressing this problem in the future. There were many reported solutions, like using System Restore, restarting the PC, logging off then back on...etc. However, there is another advanced solution for this problem. If everything else didn't work & you're comfortable using Registry Editor, read on.

IMP. NOTE: It's strongly recommended that you back up the registry before editing.

1- Click on Start --> Run, then type "regedit". (To open the Registry Editor)
2- Navigate as follows: HKEY_CURRENT_USER\Software\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\TrayNotify
3- You will find 3 registry keys: (Default), IconStreams & PastIconStream. Delete both IconStreams & PastIconStream ONLY.
4- Now open the Task Manager (ctrl + alt + delete) & go to the Processes tab.
5- Select "explorer.exe" & then click End Process. (The taskbar will disappear)
6- Click on the File menu, select New Task & type "explorer".

The taskbar should now appear again, with all the icons & everything fresh & new. Also the check-box for the Network & Volume will now be available again.
Hope I helped.

-SolaiH-

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