Registration error 408 in X-lite

I have setup up my first AsteriskNOW system in my LAN and I want to make my first call using SIP.
I use the X-lite softphone but I get registration error 408.

You can see the complete configuration of my system at the following pictures: img21.imageshack.us/gal.php?g=scr1p.jpg

What is wrong?
Where can I find a simple guide how to use Asterisk with X-lite?

Thanks in advance

Try removing the 1000 from the Authorization user name.

It’s good practice to set a secret but you shouldn’t need one.

Here are my x-lite setups if they help -

sysadminman.net/blog/archives/572
sysadminman.net/blog/archives/353

thank you for your prompt response.

I just restarted the asterisk machine and now it works fine.