New Vista install blocking Avast from start up

Hi, My niece just got a refurbed Acer desktop with Vista Home Premium 32bit. I uninstalled all of the crapware on it and installed Avast 5.0.418.

The problem is that at boot Vista blocks Avast from loading. Before I installed Avast I went into services and disabled Windows defender. Opened Windows Defender and unchecked everything so it isn't loaded or scanning anything.

Why would Vista stop my Avast from loading at startup, what good is it to have it not loading at start up when the computer is online at all time? UAC should not stop it from loading and the only way I could get it to load is by turning UAC off which I didn't want to do.

Windows 7 does not do this. Oh and I also have all of the windows updates installed.

How do I keep UAC from blocking my antivirus from loading at start up without having to click on "run this program" or whatever to get it running. I would like to keep UAC on but it's unexceptable to have to tell Vista to let run at every start up.

If she or one of her kids misses that ignores it then the computer is online with no antivirus running.

Thanks for any help, I don't remember this happening when I had Vista on my pc.

Hallo kbz1960, this should not be happening and i would suspect malware is blocking it. If you try this first & set up Avast to run as Admin. just right click on avast in the start menu select properties & then compatibility tab and select run this program as admim. then apply/ok



If this does not work try running a Boot time scan with Avast & download Malwarebytes to your desktop;

Malwarebytes.org

Then follow corrine instructions on this page;

http://www.vistax64.com/system-security/266507-internet-security-2010-virus-help-3.html

I hope this is of some help