Update UPN

#Generates a list of users from OU listed in SearchBase that have a .LOCAL upn and are enabled
$users = Get-ADUser -Searchbase 'OU=OU,DC=DOMAIN,DC=Local' -Filter {(UserPrincipalName -like '*.local') -and (Enabled -eq $true)}

#loop through each user in the list
foreach($user in $users){

    #Generates the first half of the UPN as firstname.lastname
    $upn = "$($user.Givenname)" + '.' + "$($user.Surname)"

    #sets the UPN of the account to the previously created $UPN variable @domain.local
    Set-Aduser -Identity $user.SamAccountName -UserPrincipalName "[email protected]"

    }