Offline mode is only usually automatically selected if there is no sim card in the phone, in this case, ONLY offline mode can be used, so make sure the sim is inserted correctly
Do you know if the sim card you have in the phone works in other phones?
if you have not tried, try this so you know if it's a problem with the sim card.
If it's a problem with the sim card: contact the network, and get a replacement
also try other sim cards in the N70, see it they work, if not it's either:
1) a software problem: see below of info
2) Hardware problem: if you have had the phone under a year, either contact the network OR take it to a Nokia service centre (find dtls on the Nokia site), but try the software fix first!
if you still have a prob, you can try what i told someone to do with their N73 (same applies for all N-series)...have a look here:
http://forums.overclockers.co.uk/showpost.php?p=8558915&postcount=3
Best of luck,
Lad.
