I've had a few customers recently experiencing problems where they have Calendar synchronisation issues normally resulting in errors 85010014.

In talking with our support teams and some of my colleagues it seems these symptoms and scenarios all seem to have one thing in common.  Users who have lots of recurring meetings in their diary.

Typically these take the form of weekly conference calls or status reviews. 

So why do these cause issues...?

Well on investigation with some of our support teams the recurring meetings have no end date set.  When you setup a recurring meeting with no end date - Outlook creates recurrences 400 hundred years into the future...

So in the example above of a weekly conference call Outlook would create 52x400 appointments = 20,800 appointments.

Now I'm pretty sure that your weekly conference call isn't going to be happening in 400 years time (even with the advances in modern science) so there is a simple way of avoiding this and that is to set an end date for all recurring meetings that you create.

The customers that I've had experience this have all resolved their issues by doing this so I thought I'd share it.