The exact message is
The upload of “Calendar” failed. The next upload attempt occurs with the next send/receive. Server returned an error.
Happened every time Outlook 2007 was sending and receiving – very annoying !!
I got this or so I thought shortly after receiving a published diary from a colleague. Looking under tools – email accounts – Published calendars showed no calendar.
So I clicked on change account and was shown a message saying “If you change your account, all calendars published to Microsoft Office Online will no longer be published”. Well since I don’t have any published according to outlook – I pressed continue and then sign in. It then told me I was logged into Live Id under the account I always use for that service – clicked next and finish – and was rewarded with a status screen and finally with a “Your calendar was published successfully” message. I could then send the diary to colleagues needing sight of my calendar.
So all back and working again …