pls help on nokia 3300 :(

i bought 4 units of this model from geeks.com and they have a qwerty keyboard, the guys say it is locked to ( Mobile Service Provider: AT&T Wireless, Cingular Wireless, CorrComm, LLC,.... EDGE Wireless (Affiliate of AT & T Wireless Network) , when i put my sim it turns on all fine except there is no signal, i tried a couple of uk online services to unlock but codes didnt work, gave me 'code error', do they need hardware unlock? i am listing below the details of a unit, i'd love to see your helpful suggestions.

IMEI: <removed>

Thank you.

Well, first of all, please edit your post and erase your imei. Imei posting is not allowed in this forum.

Now, if you put another sim and the phone turns one correctly, then it is unlocked. Otherwise, it'd tell you 'invalid sim'.

If you get no signal, probably the phone is working on a different frequency. IF that is the problem, there's no easy solution. Changing frequencies involves major hardware modification using specific -and expensive- equipment, replacement parts, a box in order to flash the phone, and a certain amount of knowledge not usually seen outside technicians and hardware techs.

Let's hope that is not the problem, because if it is the solution is almost limited to selling the phone to someone in a country that uses compatible frequencies.

Best regards
Edge