Hmm..
Okay first thing first.. make sure the handset in not in airplane mode, you may have to check your manual to check how to do this.
Not 100% on this but it seems like you could have a blocked IMEI, in that one of the networks have blacklisted the mobiles serial number as lost or stolen..
The unlock program may have changed the original IMEI to that of a blocked one (which is now illegal and i think can result in 10 years in prision
)
try typing *#06# into the handset and confirm with the sticker on the inside of the handset see if they match.. if they do then you are best ringing your provider to see if you can have the bar lifted.