I am having the same problem as several others. See example:
http://community.office365.com/en-us/forums/158/p/42890/147724.aspx#147724
Although I have been able to share with others, we had a new person join our group and I added them as a Licensed User of Office 365. I set the individual up with an email address, linked Outlook 2013, and we are able to share calendars. However, even after giving this person "owner" rights, I cannot share contacts with this individual user, although in the past I have successfully shared these and other contact directories with others in our group.
See image of problem:
I used PowerShell - and all user permissions appear to be set similar to other users:
Get-MailboxPermission userA and
Get-MailboxPermission -Identity UserB
I did not get this one working: Get-MailboxFolderPermission UserA:\Contacts - for I guess my formatting was off and I could not find an example as to how to type it correctly.
Has there been a general answer to this problem.
Please help and Thanks!