I couldn't sync my wife's iPhone 4 with MobileMe calendars, and in fact at one point I had worked at so many solutions I lost all the calendars completely.
When I originally activated her phone Apple strongly advised me to start a new iTunes account for her phone. But doing so unlinked her MobileMe account from the iTunes account I have, which was the account linked to MobileMe. For days she couldn't upload any iCal info to the cloud, nor could she download new calendar events.
When I tried to "sync to my Mac" (something I didn't want to do since it would then forever create multiple copies of all the calendars when I got MobileMe working again), a warning said that her account was synced to another iTunes account.
A light went off in my brain and I remembered the iTunes account I had created for her. When I logged out of that and into my iTunes account, everything synced.
In short: If you have a MobileMe account linked to a particular iTunes account, make sure all phones log onto and sync to that iTunes account or else you'll never sync with MobileMe.
For my problem, it was simple as that.
When I originally activated her phone Apple strongly advised me to start a new iTunes account for her phone. But doing so unlinked her MobileMe account from the iTunes account I have, which was the account linked to MobileMe. For days she couldn't upload any iCal info to the cloud, nor could she download new calendar events.
When I tried to "sync to my Mac" (something I didn't want to do since it would then forever create multiple copies of all the calendars when I got MobileMe working again), a warning said that her account was synced to another iTunes account.
A light went off in my brain and I remembered the iTunes account I had created for her. When I logged out of that and into my iTunes account, everything synced.
In short: If you have a MobileMe account linked to a particular iTunes account, make sure all phones log onto and sync to that iTunes account or else you'll never sync with MobileMe.
For my problem, it was simple as that.