Общий почтовый ящик

get-Mailbox "info@mydomain.ru" | select name -expand GrantSendOnBehalfTo | sort
Set-Mailbox "info@mydomain.ru" -GrantSendOnBehalfTo @{Add="bob@mydomain.ru"}
Set-Mailbox "info@mydomain.ru" -GrantSendOnBehalfTo @{Removed="bob@mydomain.ru"}

Поиск пользователей у которых адреса Mail и Targetaddress различаются

Get-AdUser -Filter {Mail -like "*"} -Properties Mail,Targetaddress |
 Where-Object {($_.mail -and $_.targetAddress) -and ($_.mail -ne ($_.targetAddress -replace "SMTP:",""))} |
 select mail,@{Expression={$_.targetaddress -replace "SMTP:"};label="Target"} | Export-Csv MismatchedTargets.csv
 
**Note** If you want narrow down your search to a specific OU, you can add the -Searchbase switch after Get-AdUser

или

Get-user -resultsize unlimited -RecipientTypeDetails "User" -OrganizationalUnit "OU=IT,DC=domain,DC=ru" 
 
get-mailuser test |fl name,WindowsEmailAddress,PrimarySmtpAddress,ExternalEmailAddress,EmailAddresses