from Michael Dawson’s linkedin group post we got the info and got the solution too in our environment , so decided to share if someone too facing this issue. thanks Michael for sharing :-)
“We recently upgraded and have been hit with quite a major issue, when an appointment is synchronized from CRM to your Outlook Calendar, Exchange freaks out when trying to send it to your Smartphone device. You get inundated with the following message:
Synchronization with your SmartPhone failed for 1 items.
The following items couldn't be sent to your mobile phone. They haven't been deleted. You should be able to access them using either Outlook or Outlook Web App.
Item Folder: Calendar
Item Type: IPM.Appointment
Item Created: 21/09/2010 16:23:34
Item Subject: 1723 MDTEST
We have called Microsoft Product Support and this is a known issue that is being researched hopefully for inclusion in Rollup13. I have been advised to uninstall Rollup12 if I want to resolve the issue and go back to Rollup11.”