If you are running Windows Update Service Pack3 (SP3) and you have a critical update KB899589 might fail and you would end up with a Red Icon on the System Tray with a notice on Windows Update about a hidden Critical update. This is a problem in Windows Update.
Basically, this update is not required for your Windows XP desktop or laptop if Service pack 3 (SP3) is already installed.
To remove these annoying notices do the following:
1. Click Start – RUN, type Services.msc and enter.
2. Double-click Automatic Updates service and click Stop. This will stop the service.
3. Now, Delete the contents of the folder
4. Now, click Start – All Programs – Windows Update. Select “Custom” and allow the scan to complete.
5. Uncheck the update KB899589 to hide it.
6. Restart the Automatic Updates service as in step 1/2
This should fix the problem or rather the annoyance.