We have a system with an Exchange 2007 server running on a separate domain to all the offices. Each office has its own server and domain. Users are set up on the local server, and a linked mailbox and (disabled) mailbox user are set up on the Exchange server. Each office is linked with fiber.
I have a user who has been working a while but without access to a shared mailbox. The user, for example, is set up on domain1, the mailbox on exchangedomain. I have given the user's mailbox full access over the shared mailbox but it still pops up saying that I am not allowed to open it. None of the other users have this issue!
I have tried
add-mailboxpermission "sharedmailbox" -user "user" -accessrights fullaccess and it still doesn't go into it.