This border is only showing in Outlook and I can't quite track it down in the the code.

Any clue?

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<td align="left" class="preheaderContent" pardot-region="preheader_content00" style="-webkit-text-size-adjust: 100%; -ms-text-size-adjust: 100%; mso-table-lspace: 0pt; mso-table-rspace: 0pt; color: #808080; font-family: Helvetica; font-size: 10px; line-height: 12.5px; text-align: left; padding: 30px 10px 20px 20px;" valign="top">Final steps of the migration to Mercer Advisors</td>
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<div style="text-align: right;">Email not displaying correctly?<br>
<a href="%%view_online%%" style="-webkit-text-size-adjust: 100%; -ms-text-size-adjust: 100%; color: #606060; font-weight: normal; text-decoration: underline;" target="_blank">View it in your browser</a>.</div>
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