Changing Domain Users’ ‘User Logon Names’ and UPN’s

KB ID 0001238 Dtd 17/09/16


Changing a users UPN suffix is easy (as long as it’s been added – see below). There is some confusion about the User Login Name though.

UPN and sAMAccountName


A few weeks ago I had a client that needed this done, (for an office 365 migration). But they had the added problem that some of their User Logon Names had spaces in them, they were in first-name{space}last-name format.

What would happen if I changed their user logon names? Would they have to use a different logon name? Would their profile break? Or worse still, would they all lose their roaming profiles?


Adding A New UPN Suffix

Before you can add a new UPN suffix you need to make it available in the domain. Administrative Tools > Active Directory Domains and Trusts > Right Click ‘Active Directory Domains and Trusts’  > Properties > Add the new Suffix  >Apply > OK.

Add a New UPN Suffix

From this point forward you can add that as a new suffix for any/all users.

The Effect of Changing a User Logon Name

Using the same user as above, I’ve changed the ‘User Logon Name’, and added the new UPN Suffix to test.

Change a Users UPN

How Does Changing a User Logon Name Affect Profile and Home Drive Paths?

Put simply it does not! To prove it I did some testing. The profile and home drive path of this user’s is set on the ‘profile’ tab of their user object.

UPN Changes and Profile Paths

It remains the same after the User Logon Name changes. When these users were setup the profile paths and home drive paths were all set ‘on mass’, by selecting multiple users and setting the path to \\server-name\folder-name\%username% and it fills in all the ‘usernames‘ with the sAMAccountName and that has not changed.

Does the User Have to Change their Logon Name?

Confusingly users don’t log on with their User Logon Name (Usually, but they can if they wanted to) from all the way back to NT4 we have logged on with the DOMAIN-NAME\USER-NAME format which uses the sAMAccountName, NOT the User Logon Name. If you look at the very first picture at the top of the page you can see that below the UPN. Its called the User name (pre-Windows 2000). You may not of even have noticed, but on Windows 10 they put this right in your face on the logon screen.

Logon Names and UPN

Whats the Point of a UPN Then?

You can actually authenticate, and log on with your UPN, (see below)

Logon with UPN

This logs on as the user in the example above with the correct profile, and group membership etc. Though it’s not common practice to logon with a UPN. Microsoft Now Have a Very BAD HABIT of telling users, (and putting in their documentation), to ‘Log on with your Email AddressThis is wrong, you actually are logging on with your UPN, Microsoft are making the assumption, that your Email and UPN are the same. This is why blogs and forums are full of scripts to change your UPN so that it matches your email address. They assume, (usually quite rightly, that if you tell users to log on with their UPN they will be confused and not know what that is). So rather than address this problem, they tell users to log on with their Email addresses. That’s the real reason we are talking about changing UPN’s, and probably why your here in the first place.

Some Users Don’t Have UPN’s?

This is normal, don’t panic, a user does not have to have a UPN, if you are seeing blank entries that user was probably migrated via a script or tool into your AD, or simply was migrated from an older version of AD as part of a domain upgrade.

So Nothing Broke?

No, the local cached copy of the profile is still named the same as the sAMAccountName;

Local Cached Policy Name

And the roaming profile and home drive also stayed the same;

Roaming Profile UPN Change

WARNING: Just so I don’t do the same thing Microsoft did and ‘Make an Assumption’. Where changing the User Logon Names would affect you is if users were already logging into their machines with their UPN, Then they would need to change their login names to the new UPN, (or use the pre-Windows 2000 login name). But I’ve never seen a user logon with a UPN, the only time I’ve ever logged onto something with a UPN, is when I can’t type a back slash to log on as DOAMIN\Username (I use a Mac). 

Remove Spaces From User Logon Names

Seriously who does this? I don’t even like spaces in folder names! Below is a PowerShell script that will search through AD and find users with a space in the middle of their logon name and replace the login name with firstname.lastname

Change the values in red.

Import-Module ActiveDirectory
Get-ADUser -Filter "UserPrincipalName -like '* *'" -SearchBase 'OU=Test,DC=pnl,DC=com' | ForEach { Set-ADUser -Identity $_.SamAccountName -UserPrincipalName "$($_.GivenName).$($_.Surname)" }

Note: If you have users with spaces in their GivenName or Surname attributes in AD this wont work, i.e if AD thinks a users first name is Juan Carlos, and the Surname is Rodriquez, then it would change the user logon name to ‘Juan Carlos.Rodriquez’ which is the very problem we are trying to fix! Also the first name and surname fields in AD have to have properties in them as well, or you will see red errors.

Change UPN Suffix For All Users Script

In the script below I’ve targeted a specific OU, but you can change the $ou parameter to point at the root of the domain, and do all users at once if you wish. Change the values in red to suit your domain.

Import-Module ActiveDirectory
$oldSuffix = ""
$newSuffix = ""
$ou = "OU=Test,DC=pnl,DC=com"
$server = "DC-01"
Get-ADUser -SearchBase $ou -filter * | ForEach-Object {
$newUpn = $_.UserPrincipalName.Replace($oldSuffix,$newSuffix)
$_ | Set-ADUser -server $server -UserPrincipalName $newUpn

Related Articles, References, Credits, or External Links

PowerShell – Update All Domain Users With Email Address From UPN

PowerShell – Updating Users Email Addresses In Active Directory

Author: PeteLong

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  1. Love you for this, thank you!!!!!!

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  2. You have saved me a ton of work been stuck over this for the last week. Thanks a million

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  3. If the user is using encryption software won’t it affect their access to files?

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    • I cant see how? UPN is simply an attribute on a user object, its GUID remains the same, if you rename a user because she is married, her security identifier is the same, i.e. you don’t have to rejoin all the AD groups she is already a member of.

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  4. Hi Peter. Please help me as I am getting error when I run the command

    You cannot call a method on a null-valued expression.
    At C:\Logging\OUs.ps1:7 char:1
    + $newUpn = $_.UserPrincipalName.Replace($oldSuffix,$newSuffix)
    + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

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    • Usually means either $oldSuffix and/or $newSuffix is empty, has an incorrect value, or does not exist.


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  5. A clear answer. It’s like finding a glass of water in the desert!

    Thanks Peter!

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