iphone 4 birthday calendar off by one day

@0815guy, it worked for me and I am using Snow Leopard.

So although I don't have iCloud support on my Mac, I do have an iCloud account which I was using to sync my contacts. So I first went to settings on my iPhone, turned off the sync of contacts via iCloud, then did the process that fortbailey describes to replace my Contacts on the iPhone.

Even if you don't have iCloud and somehow this has occurred, still worth a try to do this process?

I did the following and afterwards my birthday events seems to be correctly displayed :

- sync'ed iPhone via iTunes

- disconnected iPhone contacts from iCloud

- sync'ed iPhone via iTunes

- Enabled sync in iTunes for contacts

- sync'ed iPhone via iTunes

- Selected sync option in iTunes to overwrite contacts on iPhone with contacts from Mac

- sync'ed iPhone via iTunes

Afterwards I had each birthday twice ( on correct date ) on my iPhone !?

- connected iPhone contacts to iCloud

Afterwards only one birthday per person appears at the correct date in my calendar :-)

A lot of workarounds required to get some simple feature working. Hopefully Apple will improve future

iPhone software to handle calendar stuff better !

I had this challenge too and I fixed it easily. I made sure that my birthdays were correct on icloud contacts and calendar online. I then turned off icloud contacts on my iphone, waited a few minutes and turned it back on. Voila'

There are two problems with all this for me - any help would be appreciated.

First, I do not have an Apple Mac, I use a PC, so I am syncing my iPhone (running on IOS 5.1) with Outlook 2010 via iTunes.

Second, and this is the critical bit, for me it is not just birthdays that are wrong by a day but all repeated diary information. Back in Outlook on my PC I have set up public holidays in a number of different countries over several years (I travel a lot and need this). On my iPhone all these are off by 1 day too, so (for me at least) the problem is not just that contact information is being transferred wrongly but also Outlook calendar information.

I have tried syncing from Outlook to the iPhone in iTunes with the one-time overwrite option selected, and that makes no difference. The only solution (so far) seems to be to edit the information on the iPhone, but as has been noted there is no knowing how long that will last (and it is a real chore).

This seems to be a bug that has been around a long time - at least since the beginning of last year - and has been reported to Apple. It would be nice to feel that Apple will fix this really soon, but it looks unlikely.

Dr Bartolo, you have probable checked this, but is the date on your PC correct? A friend of mine had this problem with his Mac, it was set to the wrong timezone. Corrected this made all his calendar dates shift by one day.

If this isn't the problem, I suggest you post as a new question on the forums as many wouldn't have seen this post.

I have indeed checked this. The dates are correct both on the PC and on the iPhone.

If you look elsewhere you will find that this is a well known software bug on the iPhone and has been around for at least a year. I doubt whether anyone has an answer and I only wanted to make that more widely known in this post.

This worked for me too but I'm using .mac, not using iCloud yet. After turning off Contacts (under Settings> Mail, Contacts, Calendars > Accounts > (xxxxx.mac.com) > Contacts) then delete the contact data on your iPhone when it asks if you want to keep. After this is done then turn Contacts back on. After the phone has redownloaded the contact data the birthday issue was fixed. Seems the problem is linked to the contact data, not calendar data.

I am afraid I have to disagree. The problem also occurs to repeating dates in my calendar (see my post of 13th March above in this discussion). The inevitable conclusion is that this bug is not really a contacts problem.

Your workaround is in essence the same as mine - delete the offending repeating date and then re-enter it, when the problem disappears. But, as I have said before, for how long? Until the next iOS update? I say that deliberately because for me this problem only surfaced when iOS 5.1 was released.

I'm not sure there is much to disagree about. The fix for "birthdays off by one day" on the on the iPhone Calendar app only (not off by one day when viewing on iCal on a Mac or .Mac web based calendar), seems to be to delete the entire Contacts database on the phone then resync it from a valid source if you have one (your computer or iCloud or .Mac) or delete and add back each contact individually on your phone. Time zone settings, rebooting did not help me as it has apparently helped other people. Entire process takes only a couple minutes on WiFi as suggested by brent18berg if your synced with .Mac or iCloud.

I also had a separate problem of some duplicated events on my iPhone Calendar only,(not duplicated on .Mac web based calendar or iCal on a Mac) that was fixed in a similar fashion many weeks ago. By turning off .Mac syncing on the iPhone, deleting the calendar data file when asked, then turning syncing back on. Also only took a couple minutes to do. Did not have the additional problem with non-birthday calendar items off by one day as you seem to have had (?) while syncing on a PC with Outlook. Could that relate to corrupted calendar data?

Since the original post was re Birthdays off by a day and the fix is to delete then reinstall the contact database, either by individual or in whole, then my guess would be that this specific problem relates to a corrupted contact data file on the phone. Why this happens is way beyond me, but agree it is a recent problem. Other family members running different iPhones (3GS, 4, 4S? on iOS 5.1) synced to the same Contact database on .Mac have recently reported the identical issue, our iPad2 is unaffected so far . Also my guess is that even if the underlying cause for the corruption is identified and corrected in an update the previously corrupted contact data file may still need replacement. Good Luck and my sympathies.

There is no disagreement as such between us, but I do have a few comments on your latest post.

I do not sync with .Mac or iCloud. I do sync with Outlook on a Windows PC. The problem only appeared after iOS 5.1 came out, suggesting that this is not a problem with a corrupted database (either on the PC or on my iPhone) since I happily synced without the problem before iOS 5.1

was installed.

What this discussion highlights is that in which category of data the problem occurs is not predictable, which requires all potentially affected information to be checked for errors and then corrected (in one way or another). That is potentially time consuming (both checking and correcting).

I would only repeat that I doubt that the fix of deleting and reinstalling the contacts database will survive the next iOS update - unless Apple fix the underlying operating system bug that in my view is probably what is causing this problem, not a corrupted database. I would be interested to learn here what happens to corrected/reinstalled contacts databases after the next system upgrade.

I got my iPhone 4S a few days ago and I didn't even know what the Birthday 'calendar' was until I did a search on how to use it and found all these issues with it. So I decided to have a play...

I am synching to Outlook 2010 on my PC via iCloud. What I have noticed is that every time I edit a contact (e.g.their name) on my iPhone and allow it to sync, their birthday increments in both my phone AND iCloud databases. If I edit the contact on iCloud then it doesn't increment. I have not yet tried editing them in Outlook but will try tonight when I get home. Just thought I'd throw that into the mix of symptomes 🙂...

I was having the same issue, and this thread helped, but I eventually found out that my issue was due to Google Sync.

I went to: https://www.google.com/calendar/iphoneselect and unchecked my 'Birthdays' calender.

I am syncing my Google contacts with my iphone 4S. If I change the birthdate on my iphone then it is saved as one day ahead. I've learned never to change a birthdate on my iphone. I always go to Google contacts online and change/add the date there. Then I have no problem.