has anyone had the same issue? once a user is migrated they are unable to open shared calendar that was not migrated. I have to resend the share invitation and then it works.

1.  not sure I follow since if the calendar wasn't migrated how could there be anything to open?

2. If the actual even is there then could be the Legacy ExchangeDN issue http://www.lucid8.com/download/documentation/DSWebHelp/DigiScopeHelp.htm#TRO/Cannot_Reply_to_old_emails_or_Modify_Calendar_Items_Post_Migration.htm

my mistake the users on the old version of exchange are having issues opening up calendars of users migrated to ex2013. the ex2013 have to send out another Sharing invitation

 

ok so this is still not clear

1. You have an old version of Exchange where SOME users are still present, correct?

2. What is the older version of Exchange?

3. are the older version and Exchange 2013 within the same forest?

4. Are the older exchange version users attempting to access the exchange 2013 users calendars directly and if so why or is the issue that when they are sent invites to a meeting or??  Please provide as many details as possible

Hi,

Please check the calendar permission for the shared mailbox. Please use Outlook Online mode to open the shared calendar to have a try.

Based on my knowledge, if you were using Exchange Cached mode in Outlook with Download Shared Folders turned on, the shared calendar was cached to your local profile in Outlook. After you migrated the mailbox to Exchange 2013, the old cached shared calendar was still used with the profile in client side.

Therefore, we can either the following methods to have a try:

a. Remove the shared calendar folder from Outlook and re-add it back to lanch the new cache in Outlook (Calendar panel, Folder tab, click Open Calendar > Open shared Calendar).

b. Turn off Download Shared Folders in Outlook (File > Account Settings, click More Settings, uncheck Download Shared Folders in Advanced tab).

Regards,