Few Taskbar Icons are not coming always

Hi All,

I have a interesting problem.
Few of my taskbar icons are not coming always with every starting of my laptop.
Icons are like – Volume, Battery, Bluetooth, Wireless, Norton.
For volume and battery the check box is checked in control panel but not coming in taskbar.
If I uncheck them and click apply and again check and click apply then they come.
If I restart the machine then sometimes they come ,somtimes not.
From msconfig startup all the required options are checked still I am facing the problem.
I don’t have any virus in my machine.

Please help me.

Thanks & Regards.
-Roy