Avast Not Starting and is Preventing Other StartUp Apps from Loading

I recently did a system recovery (clean install of Windows 7) on my laptop.
After Windows was installed, I downloaded all drivers and updates using Windows Update and installed the necessary HP system software. (All of which has worked fine with Avast in the past).

After installing Avast and restarting the computer, I noticed that most of my startup items were missing from the system tray area. I restarted several more times, and it didn’t solve the problem.

As soon as I removed Avast, the startup items once again loaded normally.
I then reinstalled Avast, and the startup items once again failed to load.

At this point, I erased the hard drive and did another clean install of Windows 7 and repeated the procedure, and the same problem occured! Again, as soon as I uninstall Avast, the startup items appear normally.

I have no idea what is causing this, or how to fix it.
Has anyone else seen this problem?

I also did not see any obvious clues to the problem in the Event Viewer log.

Thats strange, never seen or heard of that one happening, is there any other security installed on the system? Microsofts Security Essentials may have been installed when you performed all the windows updates ???

Microsoft Security Essentials is not installed, I made sure of that.

What about when installing the HP system software - is it a supplied driver and software disc from HP or have you downloaded the software via the HP website ? the reason i ask is if it was a disc installation HP would have also stuck one of there trial AV’s on there ??? ( stab in the dark :-\ )

Well when I did the re-install of Windows, I used the HP recovery software, however I opted to do a minimal install, which basically installs a clean Windows 7, with only the HP hardware drivers and nothing else.

Then I updated the drivers from Windows Update and installed a few other HP specific software utilities, all of which have worked fine with Avast in the past on this machine and others.

It’s got me stumped then ??? hopefully someone else might have an idea what may be happening.

Maybe the behavior-shield is set to automatic and blocks the autostart items?

DJBone