G1 won't identify incoming calls

So recently my phone has stopped telling who is calling me and it instead displays unknown for every call I receive even if the number is on my contacts list. Outgoing calls are still fine. I've tried to restart my phone and I've tried clearing the call log. The phone isn't rooted and I have no idea what to do. Any ideas?

Can always try a factory reset. This should clear out whatever is causing the conflict with your contacts and the caller id.

This will delete any apps you have downloaded. However your contacts should be synced with googles servers and will get resynced when you boot the phone again. Same deal with your gmail emails.

Is there any easy way to create a backup file for all the apps ?

Is there any easy way to create a backup file for all the apps ?

if you have root backup for root users in the market.....and your problem is caused by a app. most likely one that identifies incoming calls.

hmm the only closely related apps are the new tmo apps and sherpa. Weird Huh?