avast! is not properly installed
ashDisp.exe is the icon (but it will not at startup itens of Windows 98, if so, nothing bat will happen anyway). On Windows 2000/XP you must have two services running in automactically mode:
avast! Antivirus - Manages and implements avast! antivirus services for this computer. This includes the resident protection, the virus chest and the scheduler, and,
avast! iAVS4 Control Service - Provides automatic updating for the avast! antivirus.
If avast tray icon missing the resident protection mau be still active (it runs by ashserv.exe and ashsimpl.exe). All of them are:
ashDisp.exe (App - actually, tray icon)
ashMaiSv.exe (App)
ashserv.exe (Service)
ashSimpl.exe (App, present only if console window is open)
aswUpdSv.exe (Service)
The task names of avast should be in Windows 2000 (as in XP):
1. ashDisp.exe (Application - actually, tray icon)
2. ashMaiSv.exe (Application - Internet Mail)
3. ashserv.exe (Service)
4. aswUpdSv.exe (Service)
5. ashSimpl.exe (Skinned Application, present only if console window is open)
The first four must be running into your OS.