thomas - have you made any further discoveries with this problem? Your description is the only one that seems to be exactly the issue i'm having.. my original post is below.
fyi - i'm genearlly not trying to sync my exchange data into the icloud.. I'm content with using outlook to give me a unified view of all calendars overlayed.
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https://discussions.apple.com/thread/3917927
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I've been working on integrating iCloud (contacts and calendar) into outlook (tried 2007 & 2010). With 3 kids I have to integrate our home and work calendars if we expect to have any chance of remembering anything.
I thought I had found a solution, using the basic windows iCloud control panel and then using a free piece of software from CodeTwo - http://www.codetwo.com/sync-for-icloud/ - which essentially just keeps any of your outlook folders (contacts, calendar, etc) in sync with one of the iCloud generated folders. One way either direction or Two way.
This all worked just fine... except...through process of elimination I found that once the iCloud control panel has generated it's iCloud 'pst' and Outlook is opening it; that Outlook takes an excruciatingly long time (minutes) to switch into the Calendar. I don't see this behavior when switching to Contacts or back to Mail. This persists even if I turn syncing for anything outlook related off at the iCloud control panel, presumably because the iCloud folders are still present in outlook. It isn't until I remove them, that things go back to normal.
Curiously, I'm doing this on two different pc's. One has normal Outlook (local files) and all works fine, while the other has an Exchange Server account, it's the one that's hanging.
windows 7 64bit
outlook 2007 & 2010 (with an exchange account)
iCloud control panel 1.1 (64 bit)
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I've since completely uninstalled office and reinstalled to be certain it was the 64bit flavor, to make sure it was playing nice with the iCloud control panel (also 64bit) - found another discussion thinking this was an issue. Found it wasn't my fix.
I do think I found the culprit. My one account in outlook is an exchange server account. So I added a second account (one of my gmail accounts) made it default, and then removed my exchange account. This fixed things right up.
There's some conflict within Outlook when you have an exchange account configured, and add the iCloud integration.