new desire won't download data for web, facebook etc

hi:)

just got a brand new unlocked htc off ebay desire to replace my iphone 3gs, all i've done is swapped the sim over.

i can ring out/in and connect with everything via wifi at home, but when i go out where i should be using 3g/2g etc nothing updates and i can't connect to the web.

it tells me to turn on mobile network, which is on in the settings:p

any ideas guys?

Have you entered the APN settings for your carrier ?

i have now cheers matey:)