Avast Premier not starting

[shailx4]

Hi,
I downloaded Avast premier 2014 from the following link.

http://www.avast.com/en-in/index

It is a 30 days trial pack. But after installing and rebooting the system, when I went to the User interface, there was a red portion in the window showing,
"You are unprotected.  The avast! service is off."
I tried clicking the 'Resolve All' and ' Start' button but no response. I tried Repairing, but still the same.
Why is that happening...??

please reply.
Thank you.

My system Specs:
Intel Penthium 4,
3.07 GHz, 1Gb Ram,
Microsoft Xp SP3

[Pondus]

what AV did you use before installing avast?
did you uninstall it before installing avast?