How does Internet Accounts on Mac Os X 10.9 and up work?

I'm having problems with trying to turn on syncing the Contacts of an Exchange email account in the Internet Accounts System Preferences with Yosemite (10.10.2).

Every time I click on the checkbox, it turns back off.

I've tried the same Exchange account on another computer, in another session and it works.

How can I make it work? Should I reset the Internet Accounts settings to the defaults. And if so, how can I do that?

More info on how Internet Accounts (~/Library/Containers/com.apple.internetaccounts) in System Preferences works since OSX 10.9 and up would be greatly appreciated!