diff --git a/usr/local/www/system_certmanager.php b/usr/local/www/system_certmanager.php
index feb62cf3d1..aaed15c5c0 100644
--- a/usr/local/www/system_certmanager.php
+++ b/usr/local/www/system_certmanager.php
@@ -777,9 +777,11 @@ function internalca_change() {
 							<a href="system_certmanager.php?act=key&id=<?=$i;?>">
 								<img src="/themes/<?= $g['theme'];?>/images/icons/icon_down.gif" title="<?=gettext("export key");?>" alt="<?=gettext("export ca");?>" width="17" height="17" border="0" />
 							</a>
+							<?php	if (!cert_in_use($cert['refid'])): ?>
 							<a href="system_certmanager.php?act=del&id=<?=$i;?>" onclick="return confirm('<?=gettext("Do you really want to delete this Certificate?");?>')">
 								<img src="/themes/<?= $g['theme'];?>/images/icons/icon_x.gif" title="<?=gettext("delete cert");?>" alt="<?=gettext("delete cert");?>" width="17" height="17" border="0" />
 							</a>
+							<?php	endif; ?>
 							<?php	if ($cert['csr']): ?>
 							&nbsp;
 								<a href="system_certmanager.php?act=csr&id=<?=$i;?>">
@@ -793,13 +795,17 @@ function internalca_change() {
 						endforeach;
 					?>
 					<tr>
-						<td class="list" colspan="3"></td>
+						<td class="list" colspan="4"></td>
 						<td class="list">
 							<a href="system_certmanager.php?act=new">
 								<img src="/themes/<?= $g['theme'];?>/images/icons/icon_plus.gif" title="<?=gettext("add or import ca");?>" alt="<?=gettext("add ca");?>" width="17" height="17" border="0" />
 							</a>
 						</td>
 					</tr>
+					<tr>
+						<td>&nbsp;</td>
+						<td colspan="3">NOTE: You can only delete a certificate if it is not currently in use.</td>
+					</tr>
 				</table>
 
 				<?php endif; ?>