Unique username and UPN with character limit

Question

Hello,

I hope someone can help me with a specific script. I have tried to put 2 or 3 together that I have found on here but not having much luck.

I am looking to have a unique username with a 10 character limit (of first name initial + surname), if not unique to add a number at the end.

I was then looking to have a unique UPN (firstname.lastname@domain.com), if not unique to add a number at the end.

Is someone able to help me put this together please?

I have come across this - https://www.adaxes.com/questions/436/check-for-duplicate-upn, but it doesn't seesm to be quite what I'm after.

Any help would be appreciated.

Answer 1

Hello,

You can use the Username has a length limitation script from the following article in our script repository: https://www.adaxes.com/script-repository/automatically-add-a-digit-to-the-username-if-it-is-not-unique-s298.htm. It works exactly the way you need.

Comments

Hey thank you for this, sorry yes this is one of the ones I tried to follow.

The issue is that it sets the UPN to the unique username.

I need it to have a unique firstname.last@domain.com (Joe.Bloggs1@domain.com).

The above is fine for the pre W2000 username, but not the UPN unfortunately.

That second part is the bit I'm mainly struggling on currently

---

Hello,

Thank you for clarifying. For us to update the script to meet your needs, please, specify the following:

1. Should the prefix part of UPN also be limited in length?
2. If the initial prefix (FirstName.LastName) is not unique, should the script add a digit to the prefix until UPN is unique? If not, what should the script do to make UPN unique?

---

Hey,

No limit to the UPN, just full first name. and last name.

And yes to your second question, simply add a digit until UPN is unique.

Import-Module Adaxes

$emailsuffix = "domain.co.uk"
$maximumLength = 10

$firstname = "%firstname%"
$surname = "%surname%"

function IsUserNameUnique($username)
{
   $user = Get-AdmUser $username -erroraction silentlycontinue
   return $user -eq $Null
}

# Get the username
$username = $Context.GetModifiedPropertyValue("samAccountName")

# Check user name Length
if ($username.Length -gt $maximumLength)
{
    $username = $username.SubString(0 , $maximumLength)
}
elseif (IsUserNameUnique($username))
{
    # Username is unique
    return
}

# If the username is not unique, generate a unique one
$uniqueUsername = $username
for ($i = 1; $True; $i++)
{
    if (IsUserNameUnique($uniqueUsername))
    {
        break
    }

    $difference = $maximumLength - $username.Length - $i.ToString().Length
    if ($difference -lt 0)
    {
        $username = $username.Substring(0, $username.Length + $difference)
    }

    if ([System.String]::IsNullOrEmpty($username))
    {
        $Context.Cancel("Unable to generate a unique username, because the number length exceeds the maximum length of the username")
        return
    }

    $uniqueUsername = $username + $i;
}

# Update User Logon Name (pre-Windows 2000)
$Context.SetModifiedPropertyValue("samAccountName", $uniqueUsername)

Function GetUserPrincipalname {



        $result = "$($firstname).$($surname)@$($emailsuffix)"  
        $int = 2
        $output = Get-ADUser -filter "UserPrincipalName -eq '$result'"
        $tmpresult = $result

        Do {
                $output = Get-ADUser -filter "UserPrincipalName -eq '$tmpresult'"

                if ($output -eq $Null) {
                    $result = $($tmpresult)
                } else {
                    $result = "$($firstname).$($surname)$($int)@$($emailsuffix)"
                    $tmpresult = $($result)
                    $int = $int + 1
                }
            }
        Until ($output -eq $Null)


    Return $result
}
# Update User Logon Name

$userLogonName = GetUserPrincipalname
$Context.SetModifiedPropertyValue("userPrincipalName", $userLogonName)
    $Context.LogMessage("The name has been changed to " + $objectName `
      + ".", "Information")

---

Hello,

Thank you for the confirmation. Find the updated script below. In the script:

• $maximumLength - Specifies the maximum length of the username.
• $upnPrefix - Specifies a template for generating the UPN prefix. You can use value references in the template. In your case, it should be "%firstname%.%lastname%"

Import-Module Adaxes

$maximumLength = 8 # TODO: modify me
$upnPrefix = "%firstname%.%lastname%" # TODO: modify me

function IsUserValueUnique($filter)
{
   $user = Get-AdmUser -LdapFilter $filter -erroraction silentlycontinue
   return $user -eq $Null
}

# Get the username
$username = $Context.GetModifiedPropertyValue("samAccountName")

# Check user name Length
if ($username.Length -gt $maximumLength)
{
    $username = $username.SubString(0 , $maximumLength)
}

# User Logon Name (pre-Windows 2000)
$uniqueUsername = $username
for ($i = 1; $True; $i++)
{
    if (IsUserValueUnique "(sAMAccountName=$uniqueUsername)")
    {
        break
    }

    $difference = $maximumLength - $username.Length - $i.ToString().Length
    if ($difference -lt 0)
    {
        $username = $username.Substring(0, $username.Length + $difference)
    }

    if ([System.String]::IsNullOrEmpty($username))
    {
        $Context.Cancel("Unable to generate a unique username, because the number length exceeds the maximum length of the username")
        return
    }

    $uniqueUsername = $username + $i;
}

# User Logon Name
$upnSuffix = $Context.GetObjectDomain("%distinguishedName%")
$uniqueUPN = "$upnPrefix@$upnSuffix"
for ($i = 1; $True; $i++)
{
    if (IsUserValueUnique "(userPrincipalName=$uniqueUPN)")
    {
        break
    }

    $uniqueUPN = "$upnPrefix$i@$upnSuffix"
}

# Update User Logon Name (pre-Windows 2000)
$Context.SetModifiedPropertyValue("samAccountName", $uniqueUsername)

# Update User Logon Name
$Context.SetModifiedPropertyValue("userPrincipalName", $uniqueUPN)
$Context.LogMessage("The username has been changed to " + $uniqueUPN `
  + ".", "Information")

---

I can't thank you enough, I kept editing my post as the more I looked at it the more problems I noticed. But still couldn't get it to work.

Your code works beautifully, the only thing is that the UPN suffix seems to be defaulting to the incorrect one.

I have specified it at the start of the code as follows: $upnSuffix = "domain.com"

But it doesn't seem to make a difference, am I missing something?

---

Sorry I've just seen that it is specified further down, I have just changed that part to meet our requirements. Thanks again :)