Multiple Outlook 2011 for Mac users are intermittently receiving error message: Error code -19813 "The send or update operation could not be performed because the change key passed in the request does not match the current change key for the item" , this occurs when they send an email. It will happen a few times and then the email will finally go through after a few attempts. They are Office 365 in the cloud. In addition, when e-mails are sent from OWA, there is no problem. I have already "Bing'd" and "Google'd" this error message and am getting very little results. Any ideas or suggestions??
