Unregistered sim and check call restrictions -34

I think it means your phone isnt unlocked( You can't use any other sim besides the one it came with)

Check this site:
http://www.ehow.com/how_7196572_activate-unregistered-sim-card.html

How to Activate an Unregistered SIM Card eHow

plug into computer and refresh software, check sim card, for corruption . replace it.

call carrier corrupt sim card??

Call restrictions are due to SIM card problems (Maybe you are using the wrong network, or your SIM card is not being detected by your phone) Another possibility is that your cellphone is restricted by the service provider. Why don't you give them a call?

I have come across this before (in South Africa) and the sim had in fact been 'deleted' either due to lack of use or somesuch. In this case the sim had to be replaced.

it could be a old sim that has been unregistered or the phone could be repoted lost or stolen but try a active sim 1st

Have you tried different sim to see if its sim or phone related? Try your sim in different phone, is it ok? Where did your K800i come from, have you just got it? Could be restricted from networks if it was a reported lost or stolen phone? (would show as emergency calls only, or unregistered sim). Check with your network provider who have access to imei data base and can tell you if its a barred handset.
Also check if phone is in flight mode as then it would not find any network? Normally allows you to select when turned off and on again.
Does it pick up any networks? If you go into settings, then networks, does it find any when you do a manual scan of networks available?
Last explanation could be faulty handset? ;( = ££££££'s

It is possible. I would check with the SP.