A quick shortcut; since $NewUserParams is already a hash, cast it to a PSCustom object.

$NewObject = [PSCustomObject]$NewUserParams

At that point you’ve got all sorts of options including ConvertTo-Html.

Personally I like to pipe to Format-List | OutString Then just slap a <PRE>...</PRE> around it. I like to use a mono-spaced font so the HTML will have the same table or list spacing just like you get in the PowerShell console. I frequently do this with Format-Table as well.

Reading through the ConvertTo-Html documentation it has the following:

Converts a .NET object into HTML that can be displayed in a Web browser.

The reason behind this behavior is Hashtables have key and value pairs opposed to PSCustomObject which is properties, so ConvertTo-Html treats them differently and you get the behavior you are experiencing.

#$ADObject | ForEach-Object {
$NewUserParams = @{
            SamAccountName    = $username
            Name              = "$firstname $surname"
            DisplayName       = "$firstname $surname"
            UserPrincipalName = "[email protected]"
            GivenName         = $firstname
            Surname           = $surname
            AccountPassword   = $securePassword
            Enabled           = $false
            Path              = "OU=$NewUserOU,$domainpath"  #change to switch based of Users Branch
            City              = $_.City
            Country           = $_.Country                  #NOTE: This Field must be the 2 digit Country Code, NOT the String Name of athe Country.
            company           = $_.CompanyName
            department        = $_.OrgDepartmentName
            Employeeid        = $_.EmployeeId
            mobile            = $_.Mobile
            Manager           = $_.Manager
            Office            = $_.Branch
            postalCode        = $_.PostalCode
            POBox             = $_.PostOfficeBox
            scriptPath        = $_.scriptPath
            StreetAddress     = $_.StreetAddress
            Title             = $_.Title



        }

        try {
            #Create the Nww user, and make them change password on first Logon
            New-ADUser @NewUserParams -ErrorAction Stop
            [PSCustomObject]$NewUserParams = $NewUserParams
            Set-ADUser -Identity $username -ChangePasswordAtLogon $true
           # $CurrentAttributes = Get-ADUser -Identity $username -Properties *
            [void]$mailBody.add("<h1>NEW User Created</h1> $($newUserParams| ConvertTo-Html)")
            #Send-MailMessage @MailParams
            Write-Host "email sent to Admin"
        }
        catch {

            throw
            Write-Warning "Could not create account $username. $($_.Exception.Message)"
        }
    }
    if ($mailbody -ne @()) {

        Write-Host "Change Added to mail"
        "$(Get-Timestamp )USER Attribute Change $mailbody" | Out-File c:log.txt -Append

        Send-MailMessage @MailParams -BodyAsHtml -body "<b>$(Get-TimeStamp): USER UPDATE </b> <p>$mailbody</p>"
    }
}

Successful output of generating HTML:

hi upon creation of a new user im wanting to take the $newuserParams, and put them in a nice formatted email. with each parameter on a new line.
ive got either the splatted params outputting all as one big line with | out-string, or i get this

IsReadOnly  IsFixedSize IsSynchronized  Keys    Values  SyncRoot    Count
False   False   False   System.Collections.Hashtable+KeyCollection  System.Collections.Hashtable+ValueCollection    System.Object   22

if i use ConvertTo-HTML

i basically want to do both but chaingin both pipes doesn’t work haha, how do i make the array populate so that i can use the ConvertTo-HTML

i want to keep it part of the $mailbody.add, as i have other things adding to $mailbody.

$NewUserParams = @{
            SamAccountName    = $username
            Name              = "$firstname $surname"
            DisplayName       = "$firstname $surname"
            UserPrincipalName = "[email protected]"
            GivenName         = $firstname
            Surname           = $surname
            AccountPassword   = $securePassword
            Enabled           = $false
            Path              = "OU=$NewUserOU,$domainpath"  #change to switch based of Users Branch
            City              = $_.City
            Country           = $_.Country                  #NOTE: This Feild must be the 2 digit Country Code, NOT the String Name of athe Country.
            company           = $_.CompanyName
            department        = $_.OrgDepartmentName
            Employeeid        = $_.EmployeeId
            mobile            = $_.Mobile
            Manager           = $_.Manager
            Office            = $_.Branch
            postalCode        = $_.PostalCode
            POBox             = $_.PostOfficeBox
            scriptPath        = $_.scriptPath
            StreetAddress     = $_.StreetAddress
            Title             = $_.Title



        }

        try {
            #Create the NEw user, and make them change password on first Logon
            New-ADUser @NewUserParams -ErrorAction Stop
            Set-ADUser -Identity $username -ChangePasswordAtLogon $true
           # $CurrentAttributes = Get-ADUser -Identity $username -Properties *
            [void]$mailBody.add("<h1>NEW User Created</h1> $($newUserParams| ConvertTo-Html)")
            #Send-MailMessage @MailParams
            Write-Host "email sent to Admin"
        }
        catch {

            throw
            Write-Warning "Could not create account $username. $($_.Exception.Message)"
        }
    }
    if ($mailbody -ne @()) {

        Write-Host "Change Added to mail"
        "$(Get-Timestamp )USER Attribute Change $mailbody" | Out-File c:log.txt -Append

        Send-MailMessage @MailParams -BodyAsHtml -body "<b>$(Get-TimeStamp): USER UPDATE </b> <p>$mailbody</p>"
    }
}