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<p dir="auto">On 6 Jan 2026, at 11:38, Robert M. Münch wrote:</p>
<blockquote style="margin: 0 0 5px; padding-left: 5px; border-left: 2px solid #777777; color: #777777;">
<p dir="auto">Hi, I'm using S/MIME to sign/encrypt my emails. The current certificate has now expired, so I got a new one.</p>
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<li>How does MM handle old emails sent to me? Are those decrypted on receive and then stored unencrypted? Does MM need to have access to the expired certificate?</li>
</ol>
</blockquote>
<p dir="auto">The latter.</p>
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<li>How does MM select the appropriate certificate? Do I have to delete the old one? Does MM only search for a valid one?</li>
</ol>
</blockquote>
<p dir="auto">There a multiple ways. You can use Keychain Access to choose the valid one, or you can enter it into MailMate's Security.plist:</p>
<p dir="auto">{<br>
map = (<br>
{<br>
address = "<a href="mailto:xxx@test.de" style="color: #3983C4;">xxx@test.de</a>";<br>
serial = "25 0E 3A 33 6D 11 4C 0E A2 FD F6 AD 6A 36 A5 FB";<br>
},<br>
);<br>
}</p>
<p dir="auto">Cheers,<br>
Sebastian</p>
<p dir="auto">--<br>
.:.Sebastian Hagedorn - Weyertal 121 (Gebäude 133), Zimmer 2.13.:.<br>
.:.IT Center University of Cologne (ITCC).:.<br>
.:.Universität zu Köln / Cologne University - ✆ +49-221-470-89578.:.<br>
.:. SIP/Webex <a href="mailto:a0620@uni-koeln.de" style="color: #3983C4;">a0620@uni-koeln.de</a> .:.</p>
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