$StudentList = Import-Csv -Delimiter "," -Path "C:\TEST\TESTLIST.CSV"
foreach ($Student in $StudentList)
{
    $StudentDisplayName = $Student.Firstname + " " + $Student.Lastname
    $StudentFirstName = $Student.Firstname
    $StudentLastName = $Student.Lastname
    $OU = "OU=CengageTest,OU=Sites,OU=Production,DC=testing,DC=tld"
    $StudentLogonName = $Student.FirstName
    $StudentLogonName = $StudentLogonName[0]+$StudentLastName
    $UPN = $StudentLogonName + "@warren.edu"
    $Description = $Student.Description
    $StudentID = $Student.ID
    $Password = $Student.Password

        $StudentLogonNameCheck = Get-ADUser -Identity $StudentLogonName | Out-Null
        $StudentLogonNameOK = $False
        $i = 2

Do {
    Try {$StudentLogonNameCheck
            Write-Host "Dupe account!"
                    if ($StudentLogonNameOK) {
                        break
                    }
                    else {
                        $StudentLogonNameOK = $True
                    }
    }
    Catch {
        $_.Exception
            break
    }
} Until ($StudentLogonNameOK)

Write-Host $StudentLogonName