$manager = "manager.mailbox@contoso.com"
$shared = Get-Mailbox -Identity shared.mailbox@contoso.com
$delegates = Get-MailboxPermission $shared.UserPrincipalName | ? {$_.IsInherited -ne $true -and $_.User -ne "NT AUTHORITY\SELF"}
Set-Mailbox $shared.id -EmailAddresses "$([guid]::newguid())@contoso.com" -EmailAddressPolicyEnabled $false -Name "$([guid]::newguid())" -HiddenFromAddressListsEnabled $true
Start-Sleep -Seconds 30
$distr = New-DistributionGroup -Name $shared.Name -DisplayName $shared.DisplayName -ManagedBy $manager -PrimarySmtpAddress $shared.PrimarySMTPAddress -Alias $shared.Alias
Set-DistributionGroup $distr.Identity -GrantSendOnBehalfTo $shared.grantsendonbehalfto -MailTip $shared.MailTip -EmailAddresses $($shared.EmailAddresses | ? {$_ -notlike "sip:*"}) -MemberDepartRestriction Closed -RequireSenderAuthenticationEnabled $false
foreach ($delegate in $delegates) { Add-DistributionGroupMember -Identity $distr.Identity -Member $delegate.user }
$delegates | ForEach {Add-ADPermission -Identity $shared.id -User $_.user -ExtendedRights "Send As"}
$delegates | ForEach {Search-Mailbox $shared.DisplayName -TargetMailbox $_.user -TargetFolder "$($shared.PrimarySmtpAddress)-archive" -LogLevel Full}