Seems like Outlook for Mac users can't a break. Windows can use Apple's MobileMe online service to wireless sync Outlook calendars with iPhones and iPads. But Mac users can't--unless they run Windows on their Mac. There are two different approaches, one using MobileMe, and another without it.
Just when Microsoft added support for Apple's syncing technology to Outlook 2011 for Mac, Apple removed it from MobileMe's calendar-depriving Outlook for Mac users from a way to wireless sync calendars with iOS devices. A few years ago, Apple enabled Windows users to sync Outlook calendars with MobileMe. Outlook for Mac users have to use iTunes and a USB cable.
When Microsoft first released Outlook 2011 for Mac last November, it didn't have any way to sync with iOS devices at all. An amazing feature hole, considering that Entourage supported Apple's Sync Services, which is what Apple uses in Mac OS X to sync to iCal, Address Book, iTunes, and, until earlier this month MobileMe.
Earlier this month, Microsoft released an update, Office 2011 Service Pack 1 (also know as version 14.1), which added support for Mac OS X Sync Services. It enabled Outlook 2011 to sync with iCal and Address Book. You can then plug your iPhone, iPad, or iPod Touch into your Mac, and sync via iTunes.
For wireless syncing, you can buy a subscription to MobileMe ($99 annually). The Mac's iCal automatically syncs with MobileMe, as do the iOS devices. Apple calls it "The easy way to keep your iPhone, iPad, Mac, and PC in sync."
Possibly, but not if you're an Outlook for Mac user. Just when Microsoft add Sync Services to Outlook 2011, Apple stopped using it for MobileMe's online calendar, replacing it with CalDAV. iCal uses CalDAV, but Outlook Mac does not.
On Windows, Apple offers the MobileMe Control Panel, which comes with iTunes 9 for Windows and later, or you can download it. The MobileMe Control Panel syncs the Outlook calendar, contacts, and email with MobileMe in the cloud, without require you to go to iTunes, or the USB cable.
Here's where virtualization comes in. If you can't use Outlook Mac, use Outlook for Windows running in a virtual machine. Parallels Desktop, VMware Fusion, and Oracle VirtualBox should all work. (Parallels offers a bundle of Parallels Desktop and Office 2010 for Windows. The company is currently offering a $20 discount on the bundle.)
There are two ways to wirelessly access Outlook from iPhone: with MobileME and without-using the free Parallels Mobile app.
Setting up MobileMe for Outlook Windows
If you're a MobileMe subscriber, you can access it from both your Mac and Windows in a VM. If you don't have (or want) iTunes installed in Windows, download the MobileMe Control Panel for Windows from within Windows. The MobileMe Control Panel runs on Windows XP, Vista, and Windows 7, and supports Outlook 2003 and later.
After you install it, you can find it from the Start menu, the Control Panel>Network and Internet. After logging in with your MobileME address and password, click the Sync tab and check "Sync with MobileMe." Choose "Automatically" if you want on-the-fly syncing to keep MobileMe and Outlook (and therefore, your iOS devide) current. Finally, click the Contacts and Calendars checkboxes and choose Outlook in the field next to the checkboxes. The Sync Now button will upload your first sync. For information about how to set up Outlook, take a look at Apple's article called Setting up Outlook for the MobileMe Calendar.
iOS/Outlook wireless calendar without MobileMe using Parallels Mobile
If you don't want to spring for the $99 annual fee there is another way: to use the free Parallels Mobile app to access Outlook for Windows on your Mac over 3G or Wi Fi. This is not really syncing, in that you directly view and control Outlook for Windows from your iOS device, similar to a remote control client like VNC or Apple Remote Desktop. There is a big difference, however: Parallels Mobile can access the VM without Parallels Desktop running.
This is pretty interesting to think about. Outlook is installed in Windows, which is installed in a virtual machine. Parallels Desktop 6 or latter needs to be installed, but not running. The Mac needs to be turned on. Parallels Mobile don't remotely control the Mac and start up Parallels Desktop. It connects directly to the dormant virtual machine and controls it.
Realistically, this solution works better on an iPad than on an iPhone or iPod Touch, though the pinch zoom is very responsive. And a WiFi network is a lot faster than a 3G network. To compensate for the latter, you can set Parallels Mobile to run in grayscale mode, turning off color and greatly lowering the amount of data transmitted. For making appointments in calendars and checking email, grayscale works just fine.
To get it running, you need to register Parallels Desktop 6. Use your registration email address and password to log into Parallels Desktop on the Mac (got to Preferences in the Parallels Desktop menu and click the Mobile icon).
On your iPad, type in this registration address and password, then type your Mac's user name and password.
There's a demo of Parallels Mobile on You Tube.
If you've tried either of these approaches