update program

Should this ask for a reboot even if it has not updated? It does each time I run it manully.
Thanks.

No it should only ask for a reboot after a Program Update actually happens.

What avast version do you have. latest 7.0.1426 ?
Why is it that you are running manual program update checks (set to Ask you will be informed if a program update it available) ?

Do you have any registry protection function/application installed ?

I have the latest version, I tried it because it seemed to be broken in the last version, works fine apart from asking for a reboot. No other security software on a clean install of windows 7 64 bit.

Check this out - avast! need to restart notification, when you haven’t just done a program update, see http://forum.avast.com/index.php?topic=28547.msg233217#msg233217.
Whilst this is a very old topic, I don’t know if that registry key/switch is still in use, but would be easy to check out if it is present.