Getting error while preparing to send sharing message

Question

I have seen many people post up about this same error, however I am going to share some details in the troubleshooting I have performed.
Environment: Exchange 2013. Cloud hosted. Internet connectivity using any number of clients. Mostly OWA, but a few Outlook 2010 and Outlook 2013.
1. User A with Outlook 2010 or Outlook 2013 right clicks on the calendar and clicks "Share" -> "Share Calendar". They look up User B in the Global Address List and click "Send." An error window pop-up states "Error while
preparing to send sharing message." User A is able to click on Calendar Permissions and add User B to the correct permissions. User A with OWA is able to right click on the calendar and click "Share Calendar" and it will send the message, no
errors.
2. User B with Outlook 2010 or Outlook 2013 on the same computer that User A was trying to do this from right clicks on the calendar and clicks "Share" -> "Share Calendar". They look up User A in the Global Address List and click "Send".
No errors and the message goes through fine. It works correctly with OWA as well.
I have seen people put up "autodiscover" and "permissions" or other things. This is obviously not a permission issue because the same thing that can be accomplished in OWA can't be accomplished in Outlook. It isn't an autodiscover issue
because the same thing that one person can accomplish on a computer/Outlook, another cannot. This is the same error that I have seen since the time of Outlook 2007 and have yet to see a valid solution.
Thanks,
Don

Answer 1

Hi Don,
Hope it is the solution:
You can't share your calendar in Outlook 2007
http://support.microsoft.com/kb/2836889
Thanks
Mavis
Mavis Huang
TechNet Community Support