I was running Win7 and had enabled mail, contacts, and calendars in iCloud, so I was able to successfully share a calendar with my wife and my iPhone and iPad. When I upgraded to Win8, I lost the link to the iCloud data, even though it's there at iCloud.com, I lost an important distribution list in my Contacts folder, and although my shared calendar is listed, I get an error when I try to select it.

I've tried deselecting mail etc from the iCloud CP app, signing out of iCloud, rebooting and signing back in to iCloud and re-enabling mail, contacts, and calendars, but that has done nothing.

Any ideas?