So this is what I see
<html>
<head>
<meta charset="UTF-8">
<title>Fuse</title>
</head>
<body style="font-family: Arial, sans-serif">
<p> </p>
<table width="463" style="border-top:3pt solid black; border-bottom:1pt solid black; padding-bottom:6pt;padding-top: 6pt;">
<tr>
<td width="181" style="font-size:10px; padding: 0px;"><strong>Fuse Graphic Design Ltd.</strong><br/>27a Synge Street<br/>
Portobello<br/>
Dublin 8<br/> <strong>01 4780802</strong></td>
<td width="153" style="color:#9b8578; font-size:12px; font-weight:bold; padding: 0px;">brand identity /<br/>brochure design /<br/> point of sale /<br/> packaging /</td>
<td width="113" style="color:#9b8578; font-size:12px; font-weight:bold; padding: 0px;">web /<br/>video /<br/> infographics /<br/><a href="https://www.fuse.ie/" style="color:#ef4036; text-decoration: none;">www.fuse.ie</a></td>
</tr>
</table>
<br/>
<a href="https://www.fuse.ie/"><img src="https://www.fuse.ie/fuselogo.gif" alt="FUSE"></a><br/>
<p style="line-height:1; font-size:10px; font-weight:bold;"><a href="https://www.linkedin.com/company/fuse-graphic-design-ltd" style="color:#9b8578; text-decoration: none;">linkedin.com/company/fuse-graphic-design-ltd</a><br/>
<a href="https://www.facebook.com/FUSE.ie" style="color:#9b8578; text-decoration: none;">facebook.com/FUSE.ie</a><br/>
<a href="https://twitter.com/fuse_design" style="color:#9b8578; text-decoration: none;">twitter.com/fuse_design</a></p>
<p style="line-height:1; font-size:12px;color:#ef4036;"><strong>NEWS! <br/>
Category WINNER Ireland e-Government Awards 2016 </strong><br/>
for EPA, Ireland’s Environment website!</p>
</body>
</html>
https://www.fuse.ie works for me; I would suggest that maybe the html checking site you’re using is not working right.
If you send an email to friend, does it work for them?