Set Up an Office 365 Shared Mailbox

Microsoft have a training video on the right way to setup an office 365 mailbox here

Altnerate reference here: Set Up a Shared Mailbox

Outlook folder Automapping

If you assign permissions to a an exchange user or folder using Powershell to a folder you can define if that Folder should be automatically displayed (or auto-mapped) when Outlook next starts.  . If a user is granted Full Access permissions to another user's mailbox or to a shared mailbox, Outlook, through Autodiscover, automatically loads all mailboxes to which the user has full access. This parameter accepts $true or $false values.

eg:

Add-MailboxPermission -Identity JeroenC -User 'Mark Steele' -AccessRights FullAccess -InheritanceType All -AutoMapping $false

Source article

Office 365 script for giving (or recinding) send-as permissions

param($mailboxname,$user)
$mailbox = get-mailbox $mailboxname

#Give user full mailbox rights

Add-MailboxPermission -Identity $mailbox -User $user -AccessRights 'FullAccess'

#Give user send-as rights to mailbox
Add-ADPermission -Identity $mailbox.DisplayName -User $user -ExtendedRights 'Send-as'

--------------

param($mailboxname,$user)

$mailbox = get-mailbox $mailboxname

#Remove user full mailbox rights
Remove-MailboxPermission -Identity $mailbox -User $user -AccessRights 'FullAccess'

#Remove user send-as rights to mailbox
Remove-ADPermission -Identity $mailbox.DistinguishedName -User $user -ExtendedRights 'Send-as'







Article source here

http://www.exchange-powershell.com/ 

Office 365 mailbox and folder permissions (with powershell)

The number of e-mail folder and mailbox permissions possible with Office 365 can be very confusing...  Below are some powershell tips on how to display the permissions followed by some tips on how to add permissions.

Viewing permissions

Using a Powershell linked session (see this post for more info) you can retrieve the permissions set at one of the following three possible hierarchical levels:

a)  Mailbox level
  b) Mailbox Top of Information Store level
    c) A Mailbox Folder level

The above hierarchical levels are hereditary by default, however can be overridden by a specific permission set at a lower level or by using a variant of the switch -InheritanceType (None | All | Descendents | SelfAndChildren | Children )

For level (a - Mailbox) use the PS > get-mailbox | get-mailboxpermission

(add | fl at the end of the command to get a formatted output)

To filter for a particular user  

PS > get-mailboxPermission -Identity username@company.com | fl

For level (b - Mailbox Top Level) use the PS > get-mailbox | get-mailboxFolderPermission

To filter for a particular user  

PS > get-mailboxFolderPermission -Identity username@company.com | fl

For level (c - Mailbox Folder Level) add :<\foldername> to the end of the indentity

PS > get-mailboxFolderPermission -Identity username@company.com:\inbox | fl

Setting permissions - in powershell

a) Adding a Top folder level permission on a mailbox name@company.com for a user "mysec"

PS > Add-MailboxPermission "name@company.com" -User "mysec" -AccessRights ReadPermission

b) Adding a Top folder level permission on a mailbox name@company.com for a user "mysec"

PS > Add-MailboxfolderPermission "name@company.com" -User "mysec" -AccessRights Reviewer

c) Adding a folder level permission on a mailbox name@company.com for a user "mysec"

PS > Add-MailboxfolderPermission "name@company.com:\inbox" -User "mysec" -AccessRights PublishingEditor

Setting permissions - in Outlook

You can set permission for a users mailbox Top Level Folder (b) or Specific Level Folder (c) from a connected Outlook client.

(b) right click on the account name and choose Folder Permissions 

(c) right click on the folder name and choose Properties.  Then click on Permissions and set them there.