My Avast! 4.8 Home Edition cannot perform automatic virus database update since 02Feb2010.
I have tried manual update by click on the iAVS Update and it is working fine.
However, the auto update still cannot work after manual update.
Please help and advise.
Thanks.
Go to settings update interval. Set 30 mins default 240 mins(min value for avast 4.8 ) Set connection no proxy and dial up via modem. If that does not work try a repair! through add and remove programs. Also what operating system are you using? 98, 2000, xp vista or 7?
Thx for reply.
I am using WinXP. I have tried to repair and auto update is working again.
Thx !!!
Wei Ni hao 
Let me tell you than avast 5.0 is out if you want to use avast 5.0,you should take some precautions:
1.Download this tool and save it anywhere(desktop recommended)
http://files.avast.com/files/eng/aswclear.exe
2.Go to uninstall the old avast via control panel[add/remove program]
3.Reboot
4.Go to safe mode
5.run the the avast uninstaller tool to remove avast completely from your computer.
6.then you can download the avast 5.0 from there
http://download.cnet.com/Avast-Free-Antivirus/3000-2239_4-10019223.html?tag=mncol