Unlocking the phone

[Guest dkothris]

Hi,

I recently acquired the unlock code from orange so that I could use my phone in the US. When i try to use a cingular card, i am granted acces to cingulars network, but when i try an ATT wireless sim any service is denied. Anyone know why? I think that at some point when i unlocked my phone (haveing inserted an ATT sim) it asked me for a network service code? which i ignored. Is it possible to specify this code again as i understand it meaning now? Maybe it will then allow me to use the ATT network, although i doubt it since it did not ask anything for the Cingular network....... can anyone help?

Thanks

[Guest Confucious]

Don't ATT use 850Mhz? I'm assuming you have a C500 from Orange in the UK which is triband 900/1800/1900 so it won't work with an operator on 850Mhz.