Hmm. It happened during an update? If the data is still in your address book make sure to open it up and immediately file > export > address book archive.
If that is a lost cause there is a slight chance there might be some data lurking in your /User/[home folder]/Library/Application Support/Address Book folder. Make a copy just in case.
In any case bad news. A couple of things.
1) make sure phone not connected > iTunes > iTunes > Preferences > Devices > if there are any backups left from before this happening put a check on disable syncing (to prevent it from being overwritten on iPhone connect) > Ok . Connect the phone. under devices in the left column ctrl+click the phone and restore from backup and choose the oldest one.
2) Maybe you exported the address book archive at some point? or exported some vcards? or synced your data with google/yahoo/mobileme? or use time machine and can go back in time a bit? ever sync with another device/computer? have the data on an old sim (you can import by slapping it in and iphone > settings > phone > import from sim)
I have had the same thing. On the 24th, with 4000 contacts in my iphone I lost all contacts around mid morning. Around lunchtime they were back, by late afternoon they were gone again.
On returning home I checked MobileMe and all my data including Calender data that I entered during the day were on MobileMe but still no contacts on my iphone.
I played around with the Push/Manual settings as described in Support but this had no effect. No spinning syncing wheel appeared when I opened Contacts.
In the end I deleted my MobileMe account from the phone, added the account again and attempted to manually sync. No spinning wheel on my phone to sync. Now I have no Contacts or Calenders.
Email though is fine so my phone can obviously connect to MobileMe, just not for Contacts and Calenders.
What is the way out of this short of a Hard Reset of my phone.
I have the same happen to me; upon returning home I hooked up to itunes and they re-appeared although it says that contacts are synced over the air.
I am wondering if it has to do with that: syncing over the air and it is timing out and the database in the iPhone is then blanked??
Painful when you need to make calls:
On Friday, October 24th I had the same problem, no contacts on my iPhone. They simply disappeared. This has happened before so I didn't panic rather I checked both my Me account and my computer and all of the contacts were there, Mobile Me just wasn't syncing. So I shut down the push feature for my contacts and re synced my iPhone to my Mac. To do this you go to "Settings" on the iPhone then "Mail, Contacts, Calendars" and then to the "MobileMe" account. There you can turn on or off contacts. I turned mine off. Then I re-synced my iPhone so that at least I had all of my contacts on the phone.
Then I checked MobileMe on line for any trouble. It turns out there was a problem with syncing that 6% of us were suffering from and that it was being fixed. So I waited until Saturday afternoon. I checked with MobileMe for any trouble and there were no problems reported.
When I had the time to fuss I went back to "Settings" on my iPhone and turned off then on again "Push" in "Fetch New Data." Then I went back to MobileMe in "Settings" on the iPhone and turned back on Contacts. Then I waited until all of my contacts were synced. This took about 10 minutes so be patient.
I hope this is a fix that works for you. Nevertheless, we should all have an easier time finding a fix for this problem on the iPhone and MobileMe Support pages. Having to find this fix in the Discussions pages seems a little "rinkydink" for Apple.
Thanks for the tip, however there's a little more to it. I also sync with an Exchange server, so when I turned off MobileMe sync the iTunes Info page said that I was syncing over the air with Exchange so couldn't to a manual sync.
So I turned off the Exchange account sync too, then re-syncd my contacts manually through iTunes to get them back. At this point, iTunes told me that my iPhone contacts were being syncd with some other user account (it didn't say which one) and that it was about to replace my iPhone contacts with the ones from my Mac. I said OK and that was that.
When I turned the Exchange sync back on on my iPhone, it said that all current contacts would be erased and replaced, I did it anyway. It was talking about the Exchange contacts, not the MobileMe ones so all was OK. I now finally have my contacts back.
Turning push back on didn't seem to cause any harm, a quick test adding a contact on my Mac, then syncing with MobileMe, showed it is working.
Having spent 48hrs and several calls to Apple Support with little help or direction I decided to restore my iPhone to factory settings. After messing around with the settings I finally got Calenders to download from mobileme. But contacts flatly refuses to do anything, no syncing wheel, nothing. Having had an issue a few weeks back when my iPhone stopped communicating with my address book via iTunes I had rebuilt my Address Book back up from scratch, minus photo's etc. I spent some time going through my Groups and performing a Sync Reset to force new data upto MobileMe.
MobileMe and my iMac are bang upto date, this I would have thought would have triggered enough of a change to force my iPhone and MobileMe to do a detailed sync via my WiFi connection.
Not a dickybird.
So I now have my Mail working fine, my Calender working fine but not one Contact transferred over.
This obviously not a unique occurrence and I am amazed that there is no tool that you can use to check that data in Address Book is in fact sound and not corrupted.
I know what Apple are going to say next - set up a test user account, wipe your phone clean and test that new account. If I had 4 days free I wouldn't mind!
I would not consider myself a Power user, but in the six weeks I have had my phone I have had three issues where syncing was a nightmare. God forbid this was to happen in Enterprise!
OK, I take it back. Just as I hit send my iPhone began to sync and all 4000 entries have appeared. At last but oh so weird.
It has been a frustrating 36hrs with no explanation as to why not one contact was on my iphone. And despite MobileMe having all my contacts matching with my Mac yet disappearing from my phone.
But they are back and everything is tickety boo!
I have been having the same problem daily since 10-24-08. While I have been traveling, several time it has completely lost all contact (Favorites and Recent Calls phone numbers remain but not the associated names). When I return to my MacBook Pro and turn it back on, the contacts will appear within about 10 minutes of performing a manual sync. I am traveling for the next two weeks and loosing all my contacts will be disasterous. Someone in Apple needs to help all of quickly. This is a major problem!
I have the same problem but it's not resolved. I'm using Exchange for push email and calendar, but use Outlook 2007 for all my contacts. After upgrading the iPhone software, it wiped out all my contacts and won't re-sync with the personal folder of my Outlook. It would only sync with the Contact folder in the Exchange account I have in my Outlook. I have also spent many hours and just can't get it to work. Short of disabling the Exchange account either in my Outlook or in the iPhone, I don't see any other way to resolve this. I am not using MobileMe from Apple. Anybody with similiar experience?
Just chiming in. I have had the same problem but it seems to be getting more frequent. Today lost contacts and had numbers only for favorites/recents for the entire day. Chatted with mobile me support via site but nothing seemed to work. I had my address entered as .mac instead of .me (never a problem before) but they thought it might help to delete and create a new account using .me. I did this to no avail (just lost my calendar also). Then deleted that and reentered the .mac account info and finally it worked (but took a while to sync my 3500 contacts over wifi).
this has been happening to me lately but my issues seems to be a bit different from yours....
my iphone syncs with phone, calender and address book on my imac. well one day my imac decided to restart ichat to factory settings, unbeknownst to me I synced my phone and for reason my computer (and ichat and its connection with my address book??) synced OVER the massive amount of people in my contacts on my phone.
apple support did not give me a solution.
ichat reset itself again yesterday, i realized this first and I havent been able to sync my phone since.....
how do we fix that?