Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Fixing MobileMe Syncing Problems
MobileMe is quite easy to install and use. But sometimes there are problems in syncing and you are unable to receive or send data. This happens to a lot of people.
You can reset sync data by taking a complete copy of data and circulating it through every system. Select one system that will act like primary Mac.
Turn off MobileMe syncing
On Mac, open System Preferences and select MobileMe. Now click on Sync and uncheck the option of synchronizing with MobileMe.
On iPad or iPhone, go to Settings and select Mobile me from Mail, Contacts, and Calendars. Turn off the Contacts and Calendars options.
Backup data on primary Mac
When you merge data on various devices, it can lead to problems. Your Calendar and Contacts databases are in the home folder in the Library.
Contacts: Go to library in home folder. Select Application Support and go to Address book.
Calendar: Go to library in home folder. Select Calendars.
Select these folders and copy them into a backup medium.
Now that syncing is disabled, you can re-enable the syncing on primary Mac and change the sync setting to Manual. Click on Advanced option in Contacts.
In the next window, choose primary Mac and then reset the sync data. After resetting, the initial sync might take a bit longer than usual. After syncing, check your information on MobileMe website and your Address book to check if things are ok. Change an entry in the Mac and then select Sync now. If everything is fine, do the same with Calendars.
If you are on iPad or iPhone, select Mail from Settings, and then MobileMe. Now re-enable the previously turned off items.
Nuclear options for resetting syncing and deleting accounts
If the previous method doesn’t work, there are other options too. There is hidden preference on Mac for resetting syncing. There will be a MobileMe icon in menubar. Click on it and select Reset Sync services. Now the sync services will be reset.
If it still does not work, then you can use Unix commands to fix the problem.
iPads and iPhones
Delete and make MobileMe account again. Select Delete Account from Edit. Now reboot the iPad or iPhone and add new MobileMe account. This will replace all data and syncing will return to square one.
We hope you don’t have any problems with MobileMe syncing. But if you do, you know which steps to take.
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