PowerShell: Fix Email Aliases as Preparation for O365 Migration

Check SMTP Addresses of On Premise Mailboxes

function checkSmtpAddresses{
    $microsoftDomain1="@kimconnect.mail.onmicrosoft.com"
    $microsoftDomain2="@kimconnect.onmicrosoft.com"
    $dotLocal=".local"
    $onpremMailboxes=Get-Mailbox -ResultSize unlimited | Select-Object Alias,@{Name="Domain";Expression={$_.PrimarySmtpAddress.Domain}}
	foreach ($item in $onpremMailboxes){
        $output="";
        $username=$item.Alias
        $mailbox = Get-Mailbox -Identity $username
        $smtpAddresses=$mailbox.EmailAddresses | Where-Object {$_.SmtpAddress -ne $null} | select smtpaddress
        $matchDotLocal=$smtpAddresses | Where-Object {$_ -match $dotLocal}
        $matchMicrosoftDomain1=$smtpAddresses | Where-Object {$_ -match $microsoftDomain1}
        $matchMicrosoftDomain2=$smtpAddresses | Where-Object {$_ -match $microsoftDomain2}
        if($matchDotLocal){$output="dotLocal domain is detected for this mailbox. Please consider removing it. "}
        if($matchMicrosoftDomain1){$output+="$microsoftDomain1 domain detected. "}
        if($matchMicrosoftDomain2){$output+="$microsoftDomain2 domain detected. "}
        if(!($matchMicrosoftDomain1) -and !($matchMicrosoftDomain2)){$output+="this account has no SMTP email addresses. "}
        "$username`: $output"
        }
}

Sample Output:

testaccount1: @kimconnect.mail.onmicrosoft.com domain detected.
testaccount2: @kimconnect.mail.onmicrosoft.com domain detected.
testaccount3: @kimconnect.mail.onmicrosoft.com domain detected.

Fix SMTP Addresses:

# This script fixes all on premise mailboxes to prepare them for migration to Office 365
# 1. Remove non-routable dot local domainSuffix
# 2. Add Microsoft Email addresses
# 3. Replace email address using an old domain suffix with a new domain suffix

# Set variables here
$microsoftDomain1="kimconnect.mail.onmicrosoft.com"
$microsoftDomain2="kimconnect.onmicrosoft.com"
$dotLocal=".local"
$oldDomain="kimconnect.org"
$newDomain="kimconnect.com"

function generateBatch{
	"Generating batch by collecting information on all mailboxes..."
	$GLOBAL:batch=Get-Mailbox -ResultSize unlimited | Select-Object Alias,@{Name="FixedPrimaryEmail";Expression={if($_.PrimarySmtpAddress.Domain -like 
	$oldDomain){"$Alias@$newDomain"}else{$_.PrimarySmtpAddress} }}
	
	# Test with 2 records
	#$GLOBAL:batch=Get-Mailbox -ResultSize 2 | Select-Object Alias,@{Name="FixedPrimaryEmail";Expression={if($_.PrimarySmtpAddress.Domain -like #$oldDomain){"$Alias@$newDomain"}else{$_.PrimarySmtpAddress} }}
}

function setPrimarySMTP ($alias,$newEmail){
		Set-Mailbox $alias -EmailAddresses @{add="$alias@$newDomain"}
        $mailbox = Get-Mailbox -Identity $alias
        $primaryDomainCurrent=$mailbox.PrimarySmtpAddress.Domain
        "Comparing existing email domain with $primaryDomainCurrent if it matches $oldDomain. If so set desired email as $newEmail..."
        
        if ($primaryDomainCurrent -like $oldDomain){
            "Primary SMTP email adddress for this user is $primaryDomainCurrent. Updating email address to $newEmail... "
            $mailbox.EmailAddresses += $newEmail
            $mailbox | Set-Mailbox -EmailAddressPolicyEnabled $False -PrimarySmtpAddress $newEmail
        }else{
            "Primary SMTP email address is already matching the desired domain. Skipping this record."
            }        
}

function removeDotLocal($alias){
    $mailbox = Get-Mailbox -Identity $alias
    $smtpAddresses=$mailbox.EmailAddresses | Where-Object {$_.SmtpAddress -ne $null} | select smtpaddress
    $matches=$smtpAddresses | Where-Object {$_ -match $dotLocal}
    if ($matches){
        foreach ($match in $matches){            
            $matchedDotLocal=$match.SmtpAddress
            "Removing $matchedDotLocal..."
            Set-Mailbox $alias -EmailAddressPolicyEnabled $False -EmailAddresses @{remove="$matchedDotLocal"}
        }
    }
}

function addMicrosoftEmails{
	Set-Mailbox $username -EmailAddressPolicyEnabled $False -EmailAddresses @{add="$username@$microsoftDomain1"}
    Set-Mailbox $username -EmailAddressPolicyEnabled $False -EmailAddresses @{add="$username@$microsoftDomain2"}
}

function fixEmailAliases{
	generateBatch;
	foreach ($item in $batch){
		$username=$item.Alias
		$primaryEmail=$item.FixedPrimaryEmail
		"Processing $username with primary email as $primaryEmail..." 
		addMicrosoftEmails;    
		removeDotLocal $username;
		setPrimarySMTP $username $primaryEmail;
	}
}
fixEmailAliases;

First Draft Version:

Make a batch file named “C:\Users\kimconnect\Desktop\batch1.csv”:

Display Name,Alias,Primary SMTP Address,EmailUsername,Domain,FixedPrimaryEmail
Kim Connect,kconnect,[email protected],kconnect,kimconnect.org,[email protected]
Bruce Lee,blee,[email protected],blee,kimconnect.org,[email protected]
Chuck Norris,cnorris,[email protected],cnorris,kimconnect.org,[email protected]

Run this script As Administrator in Exchange PowerShell:

$batchfile="C:\Users\kimconnect\Desktop\batch1.csv"
$dotLocal=".local"
$domain="kimconnect"
$domainSuffix=".com"
$primarySmtpDomain="kimconnect.com"
$oldDomain="kimdisconnect.org"

$batch=import-csv $batchfile

function setPrimarySMTP ($alias,$newEmail){
        $mailbox = Get-Mailbox -Identity $alias
        $primaryDomainCurrent=$mailbox.PrimarySmtpAddress.Domain
        "Comparing existing email domain with $primaryDomainCurrent if it matches $oldDomain. If so set desired email as $newEmail..."
        
        if ($primaryDomainCurrent -like $oldDomain){
            "Primary SMTP email adddress for this user is $primaryDomainCurrent. Updating email address to $newEmail... "
            $mailbox.EmailAddresses += $newEmail
            $mailbox | Set-Mailbox -EmailAddressPolicyEnabled $False -PrimarySmtpAddress $newEmail
        }else{
            "Primary SMTP email address is already matching the desired domain. Skipping this record."
            }        
}

function removeDotLocal($alias){
    $mailbox = Get-Mailbox -Identity $alias
    $smtpAddresses=$mailbox.EmailAddresses | Where-Object {$_.SmtpAddress -ne $null} | select smtpaddress
    $matches=$smtpAddresses | Where-Object {$_ -match $dotLocal}
    if ($matches){
        foreach ($match in $matches){            
            $matchedDotLocal=$match.SmtpAddress
            "Removing $matchedDotLocal..."
            Set-Mailbox $alias -EmailAddresses @{remove="$matchedDotLocal"}
        }
    }
}

function fixEmailAliases{
  foreach ($item in $batch){
    $username=$item.Alias
    $primaryEmail=$item.FixedPrimaryEmail
    "Processing $username with primary email as $primaryEmail..."   
     
    Set-Mailbox $username -EmailAddresses @{add="$username@$domain.onmicrosoft.com"}
    Set-Mailbox $username -EmailAddresses @{add="$username@$domain.mail.onmicrosoft.com"}
    Set-Mailbox $username -EmailAddresses @{add="$username@$domain$domainSuffix"}
    removeDotLocal $username  
    setPrimarySMTP $username $primaryEmail
    
  }
}
fixEmailAliases;