ITunes was unable to load data class information from Sync Services. Reconnect or try again later.

Ever since I upgraded to iTunes 10.4 I've been getting this dreaded message on many occasions when I try to sync my iPhone 4 or iPad 2 with my Win 7 64 bit machine. "iTunes was unable to load data class information from Sync Services. Reconnect or try again later." What happens is that local content (music, videos etc) will sync properly to my iPhone, but other content (such as Outlook information, MobileMe stuff, etc) will not.
I have uninstalled and completely purged all Apple data from my PC (including hidden files and folders under Common Files and in the Registry) and reinstalled iTunes. Yet after one or two syncs, the same problem resurfaces. The other weird part is that the Sync Services crap-out message will happen after I do a successful sync, leave the iPhone connected to the PC, and don't even touch the computer for several hours.
I've actually developed a very tedious work around that seems to restore syncing if for a short time.
- Undock/unconnect all Apple devices from the PC.
- Close iTunes, MobileMe control panel, and Safari (if you have it).
- Start Task Manager (Ctrl + Alt + Del) and shut down iTunesHelper.exe and SyncServer.exe
- Open up a Windows Explorer window (like My Computer) and under Tools, Folder Options, View, toggle on Show Hidden Files and toggle off Hide Protected Operating System FIles
- In WIndows Explorer, navigate to "C:\Users\<your name>\App Data\Roaming\Apple Computer". Rename the folder Sync Services to something else, like Sync Services_Old.
- In WIndows Explorere, navigate to "C:\Program Files (x86)\Common Files\Apple\Mobile Device Support" and double-click on AppleSyncNotifier.exe.
- Go back to your Folder Options and turn off SHow Hidden Files and toggle on Hide Protected Operationg System Files
Now you can start up iTunes again and connect your device. It should sync properly again (at least, until it doesn't once more).
Does anyone at Apple have any idea about this error or a solution?

I actually spent a fair amount of time on the phone with a senior Apple tech last week. He directed me to this topic:
http://support.apple.com/kb/HT1923?viewlocale=en_US
It's important that you go through the steps EXACTLY as described here and in the proper order. Also make sure MobileMe control panel is uninstalled (if you have it).
Interestingly, when I went through this procedure and then reinstalled iTunes 10.4 64-bit  (didn't do MobileMe or Safari at this stage, but QT is automatically installed) everything worked perfectly. The aforementioned error messages disappeared and all is working flawlessly, as it should.
I hope my expereince will help! Give it a try.

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