Get User Primary SMTP Address without Exchange module

Have you ever found yourself in need to find user primary SMTP without having access to Exchange cmdlets? Usually checking the email built-in attribute is enough but there are situations where field is either empty or not properly aligned with user’s primary SMTP address.

Here’s a way to do it:

$testUser = Get-AdUser -Identity 'Test.User' -Properties 'ProxyAddresses'
[string]$primaryAddress = $testUser.'ProxyAddresses' -clike 'SMTP:*'

A user can only have a primary address denoted by the SMTP prefix. In the above example we are performing a case sensitive like operation on the ProxyAddresses attribute which will return only the primary address.

Of course the same approach can be used when dealing with multiple users

[array]$matchingUsers = Get-AdUser -Filter * -Properties 'ProxyAddresses'

foreach ($user in $matchingUsers)
{
  [string]$primaryAddress = $testUser.'ProxyAddresses' -clike 'SMTP:*'

  # Take any required action
}