Windows xp battery icon not updating
In Vista, if the Clock, Network, Volume and Power icons have disappeared and when you go into properties on the taskbar and look at "System Icons" under the "Notification Area" tab, Volume, Network, and Power are greyed out, then visit Paul's Forum and run his fixing program. reminds us that, if other icons disappear for good and never reappear, we should check first whether the programs are started at all.
Check your Startup folder and the starter registry entries through Start, Run..., type: msconfig, press Enter, to check whether the programs are really started at system start, or use Task Manager (Ctrl Shift Esc) to see whether the processes are running.
This has nothing to do with the hide inactive icons settings.
According to the excellent analysis in the Problem analysis and proposed solution comment by tasmanian this is caused by a timing defect in the Windows function Shell_Notify Icon in shell32.dll, which has a timeout fixed at 4 seconds.
Combined with an unfavorable Windows API message this causes the problem, which befalls many heavily loaded computers that don't have ultra-fast hard disks.
Right-click the task bar, click on Properties, uncheck the last check box.
You can reactivate it later if all other problems are identified or solved.