Problem:
You need a list of all users and aliases
Solution:
Get-Mailbox | Select-Object DisplayName,@{Name=“EmailAddresses”;Expression={$_.EmailAddresses |W here-Object {$_ -LIKE “SMTP:*”}}} | Sort | Format-List
Or
‘ Get-Mailbox | Select-Object DisplayName,@{Name=“EmailAddresses”;Expression={$_.EmailAddresses |Where-Object {$_ -LIKE “SMTP:*”}}} | Sort | Export-Csv <file path i.e. C:\Users\admin\Desktop\test.csv>