The exact cause for the problem is unknown. According to Microsoft, the
problem can be caused by the Simple Service Discovery Protocol (SSDP)
which discovers Universal Plug and Play devices on your network.
However, Microsoft Knowledge Base may not exactly the same symptom with
notification area icons do not appearing issue, as it also has other
symptoms:
The pointer changes to an hour glass when you move it over the taskbar.
Some icons do not appear in the notification area.
When you click Start, nothing happens.
The Start button does not work for several minutes, and then it starts
to work.
When you restart the computer, the icons in the notification area are
missing. If you log off and log on with the same user account, the icons
appear.
When you click any icon in the Quick Launch bar immediately after
starting the computer, the pointer changes to an hourglass.
Solutions
Possible solutions are many, although none confirmed to be working
perfectly. If you have the symptoms as mentioned by Microsoft above, you
can try out resolution suggested by Microsoft to resolve this behavior.
Note that Microsoft’s solution will disable the SSDP Discovery Service,
which caused new devices on the network cannot be found automatically.
1. Right-click My Computer, and then click Manage.
2. Click Services and Applications.
3. Double-click Services.
4. In the Services list, right-click SSDP Discovery Service, and then
click Properties.
5. On the General tab, in the Startup type drop-down list, click Disabled.
6. Click OK.
If it doesn’t work, the alternative would be disable both SSDP Discovery
Service and Universal Plug and Play Device Host. Repeat the above steps
for both services.
You may try to choose Automatic at step 5 instead of Disabled, as it’s
reported some people has success with this.
If you need Universal Plug and Play services and wouldn’t want to
disable it, Francesco Ostuni suggested Ostuni Workaround which does not
disable the uPNP service. The steps as below (only applicable on Windows
XP with Service Pack 2):
1. Open My Network Places.
2. Click Hide Icons for Networked uPnP Devices at the Tasks panel.
3. For Windows Classic theme users, click Tools and the Folder Options
in Windows Explorer, and then select Show Common Tasks in Folders to see
the option specified in step 2.
Or,
1. Open Control Panel.
2. Click Add or Remove Programs.
3. Click Add/Remove Windows Components.
4. Select Networking Services.
5. Click Details button.
6. Uncheck (remove) the UPnP User Interface.
7. Click OK.
The most reliable way to solve the problem is to logout and then login
again to Windows XP.
If you don’t want to logout and login Windows XP after starting the PC,
Disable Automatic Logon is a possible way to solve the issue by the
following steps:
1. Click on Start.
2. Click on Run.
3. Type “control userpasswords2″.
4. Click OK.
5. Check (Select) Users must enter a user name and password to use this
computer.
6. Click OK.