I am a die-hard MobileMe fan. I use MobileMe to wirelessly sync my contacts, calendars, mail and more among three computers and my iPhone. In general, MobileMe syncing is phenomenal. Unfortunately, it’s not flawless.
The first thing to do when troubleshooting a MobileMe issue is to identify which device (i.e. Computer or iPhone) is having the issue. The best way to do this is to first check your MobileMe Cloud by logging in to www.me.com. If none of your data is on there then syncing is not working from any of your devices. If your data is on there, see if you can figure out which device is having the sync issue by adding a new calendar item or contact to your devices and then force a sync.
On an iPhone, the syncing will be automatic. On your computer, you can force-sync by going to the Sync icon in your menu bar (it looks like two arrows chasing each other) and select “Sync Now.” Then, reload the MobileMe Cloud website and see which device successfully synced the data and which device did not.
In general, most MobileMe sync issues can be resolved by simply toggling synchronization on and off. For example, if my contacts aren’t syncing to my phone I’d go to Settings > Mail, Contacts, Calendars > My MobileMe account and toggle the “Calendar” switch off and back on again. If the issue was that my phone was syncing fine but the data wasn’t getting to my computer, I’d go to System Preferences > MobileMe > Sync and uncheck “Synchronize with MobileMe” and then tell it to sync again.
Sometimes, resetting MobileMe syncing does not resolve the issue, and then you need to dig a little deeper. First off, make sure it’s not user error. Check syncing preferences on both your iPhone and your computer and make sure they’re set appropriately. Next, make sure you’re looking at the right screen on your iPhone.
For example, if you think your contacts are not syncing with your iPhone, be sure you are viewing the “All Contacts” screen. If you think your calendar is not syncing to your iPhone be sure you’re viewing “All Calendars” and not just an individual calendar on your iPhone.
The issue that I ran into today while helping a client was a “data integrity error” that he received when attempting to sync his calendar from MobileMe to his computer. In this situation, I had to reset his sync preferences. First, I backed up his calendar in iCal. Next I reset the sync preferences by disabling MobileMe syncing in System Preferences. Then I opened iSync and ‘Reset Sync History’ in preferences. I then re-enabled syncing and, when prompted, I told MobileMe to replace all data on the computer. So far so good!
It should be noted that there are different ways to reset syncing depending on what version of the operating system you use. The above scenario was in 10.5.8. Apple has three great articles on how to resolve MobileMe sync issues:
MobileMe: Troubleshooting iPhone or iPod touch sync issues
Mac OS X v10.5, v10.6: Resetting the SyncServices folder
Sync Services: Advanced troubleshooting for contact and calendar syncing
Check those articles out if you need further help. Happy syncing!