At last I find the follow in the FAQ'S:
[ How can I uninstall avast!?
A: You can uninstall avast! just as any other software - using ADD/REMOVE PROGRAMS in Control Panel. There is nothing special about this. If any problem appears, use the avast! uninstall utility.
The exact way:
Click on START button.
Select SETTINGS -> CONTROL PANEL (or simply CONTROL PANEL - it depends on your Windows version) -> ADD/REMOVE PROGRAMS.
From the list of installed applications select avast! Antivirus and click on CHANGE/REMOVE button.
avast! setup starts. Select UNINSTALL and click on NEXT.
Computer restart will be needed after avast! uninstallation.]
I find the control panel with clicking on the list of installed applications and click on "change/remove" button,now I clicked on the area "repair".
Note: the problem is not repaired!!!!!!!!!!