hi, a few weeks ago i starting migrate exchange 2010 to 2013,   migrate 50% of users  and everything worked fine,  but yesterday noticed that client in their outlook calendar,cannot add meeting to room mailbox calendar, erros says that they not have permission

when i chac folder permission from administrator user it says

i today migrate all users, room mailbox and system mailboxes from old exchange to new exchange but no eny change,  

what can i do ?

Hi,

Please check this in OWA.

Meanwhile, check the permission on the room mailbox.

Get-MailboxPermission Room | fl AccessRights,User

And does this issue occur on all room mailbox?

Best Regards.