How can I fix missing System Tray Icons in WinXP: USB drive and so on?

Q. How can I fix missing System Tray Icons in WinXP: USB drive and so on?
A.
1. Right-click My Computer, and then click Manage.
2. Expand Services and Applications.
3. Double-click Services.
4. In the Services list, for SSDP Discovery Service and Plug and Play, right-click and then click Properties.
5. On the General tab, in the Startup type drop-down list, click Automatic.
6. Click OK.
7. Restart computer.
After that your computer will discover Universal Plug and Play devices.