Disconnected means your ATA is not talking to the FPL server
FPL are not very forth coming with help to people that just buy the config files, so it would probably be not worth your time calling in.
The next thing I would try is removing the ATA out of the equation for a moment - just to make sure your account is set up right. Download a free SIP phone (not the FPL desktop one) and set that up with your details. I always use the 3CX one, but there are lots others like x-lite
Windows
http://www.3cx.com/downloads/3CXPhone6.msihttp://www.counterpath.com/x-lite-5-for ... nload.htmlMAC
http://www.counterpath.com/x-lite-5-for ... nload.htmlhttp://www.macupdate.com/app/mac/23969/isoftphoneSee if you can get connected with one of those. If so, it looks like your ATA is not set up right, so do a complete reset and go though the settings again. If not, it is either something on your network that is stopping VOIP connections or your account is not set up right possibly. From there I would probably go to a friends house and try on their network, or ask nicely for a member of staff here to try your account details.
**One thing I should have mentioned is, this section is not for problems but more for how-tos, so don't expect your thread to stay here when a staff members sees it, it will be moved to the correct sub forum.