Check out this Sample Code:
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office">
<head>
<title></title>
</head>
<body style="font-family: Arial; margin: 0; padding: 0;">
<table align="center" width="600" cellpadding="0" cellspacing="0" border="0" style="width: 600px; background-color: #000000; font-family: Arial; font-size: 15px;color: #ff0000;">
<tr>
<td style="padding:10px;font-weight: bold;font-size: 20px; color: #ff0000;">Header Title</td>
</tr>
<tr>
<td style="padding:10px;">This is the content for this section.</td>
</tr>
<tr>
<td style="padding:10px">
<a href="#" target="_blank"><img src="LearnMore.png" width="170" height="38" border="0" alt="Learn More" /></a>
</td>
</tr>
</table>
</body>
</html>
This code snippet pertains to Office 365 on Windows 10
Most other email clients display correctly.
Tried some solutions mentioned here
It seems that using a font size of 12px or 16px eliminates the line, but the specified preference is to use 15px
The expected outcome should be...