Systray missing (WinXP)
Navigate to the key
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer
In the right pane look for a value named "NoTrayItemsDisplay". If so, remove it or set it the value "0”.
There are other causes, review this KB article:
**/Icons in the Notification Area May Disappear If You Use High-Contrast Color Themes in Windows XP
http://support.microsoft.com/kb/321213/en-us
if you want to, there exists a script for doing these steps in an automatic way


