If you look at the source of the email (through your email client), you'll see that when the email is sent out, both the PLAIN and HTML versions are sent together. My understanding is because it is up to the email client to choose which version it can/wants to display.


TEXT/PLAIN:
Code
--b1_99999999999999999
Content-Type: text/plain; charset=us-ascii

BritBike Forum
-------------------------------

Hello id242,

This is a test email from ...


TEXT/HTML:
Code
--b1_99999999999999999
Content-Type: text/html; charset=us-ascii

<html>
<body>
<table style="width:100%;padding:0;border-spacing:0;">
<tr>
<td style="border-collapse:collapse;  font-family:arial,helvetica,sans-serif;" >
<table style="width:100%;padding:0;border-spacing:0;">
<tr>
<td style="background:#f7fdff; border-top:6px solid #104eb1; border-bottom:1px solid #000; color:#000; font-size:18px; font-weight:700; padding:10px; text-align:center;" >
BritBike Forum
</td>
</tr>
<tr>
	<td style="background:#fff; font-size:14px; padding:6px 6px 10px;" >
		<span style="font-weight:700;">Hello id242,<br><br></span>
		This is a test email from ...


View the source of the received email. I use Gmail when I signed up on your forum a few years ago smile