First check that ashDisp.exe is running in windows task manager ?
Second I assume you have checked it isn't hidden by clicking the < icon to the left of the clocl ?
What other security software do you have ?
Some monitor and stop new start-up items.
As a temporary measure until this is resolved you can create a desktop shortcut for this file C:\Program Files\Alwil Software\Avast4\ashDisp.exe (the avast icon and interface to the providers). Right click on the file and select Send To, Desktop (create shortcut). You will need to run this after each boot until the problem is resolved.
Check the option in the Appearance tab of Program Settings. Or Make a link to ashdisp.exe in your startup folder.