Resident scanner doesn't work

Avast works well, but since I’ve had it I wondered how it can prevent virus’s from getting on my computer without a program running at all times, then I read the help file and found out there is supposed to be a small icon in the taskbar, and there isn’t. If you know how to fix it or if you have the same problem please help. I have windows XP

Hello and welcome to forums :slight_smile:

First try to download first file (file: eicar.com) from this page:
http://www.eicar.org/anti_virus_test_file.htm

If you get avast! warning than the scan engine is working,but there is no icon in treybar. Oh and this is not a real virus,just a test file to check if antivirus is working properly.

Do you have any other antivirus installed in your system?
Did you boot after installation?

If you click CRTL-ALT-DEL simultaneously, did you see ashDisp.exe running?