Windows Genuine Advantage notification checks genuineness of Windows XP. It validates it against black listed serial numbers. And if your serial number is listed there you would likely to recieve this error message in your tray. But there is nothing to be worry about this is not virus, its just a reminder to purchase an orignal copy from Microsoft.

So this is the first solution to get rid off this :}. Second solutions is to make some tweaking so that you wouldn’t see it again. You can found many tweaks on Internet but following just required speed and it will done.

• Open Task Manager, there you will notice process of WgaTray.exe running
• Go to C:\Windows\System32\ and locate WgaTray.exe and select it
• Now You need to kill the process and instantly delete the .exe file from system32 folder before it run again in Task Manager. When confirmation of ending process appears you should have opened System32 folder. The moment you press enter, put your focus on folder window and delete the exe (which you already selected). By going through this sequence you will be end up with removal.
• After deletion from System32 go to C:\Windows\System32\dllcache\ and delete WgaTray.exe here also
• Go to C:\Windows\System32\ rename WgaLogon.dll to WgaLogon.dll.bak and create an empty file and name it WgaLogon.dll
• Copy this .dll file to C:\Windows\System32\dllcache\ too

Now restart you Windows and you will see its gone. Turn off your Automatic Updates to prevent its occurrence again.