There are 5 avast processes running in the image, so you are saying you only have that one, if so the security center is correct avast isn't running.
If you click on the avast 'a' icon (ashDisp.exe in the task manager) do you get any errors, I suspect you do, if so what are they ?
So this system didn't come pre-installed with an AV (which is common on some systems) ?
Do you have any other security software installed, anti-virus, registry protection, etc. ?
Did you install this from an account with Administrator privileges and did you jump through any Vista UAC hoops ?
It may be that your installation is corrupt, so a clean reinstall might be best:
Download the latest version of avast
http://www.avast.com/eng/download-avast-home.html and save it to your HDD, somewhere you can find it again. Use that when you reinstall. Ensure that you scroll down and select the avast direct download link for the English version and not Cnet as that is for an on-line installation (not what you want to do). - Direct download for avast Home, English version,
http://files.avast.com/iavs4pro/setupeng.exe.
Download the avast! Uninstall Utility,
find it here and save it to your HDD.
- 1. Now uninstall (using add remove programs, if you can't do that start from the next step), reboot.
- 2. run the avast! Uninstall Utility, reboot. If step 1 failed it may be necessary to run this from safe mode, once complete reboot into normal mode.
- 3. install the latest version, reboot.