diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -257,7 +257,6 @@
     'ConpherenceConstants' => 'applications/conpherence/constants/ConpherenceConstants.php',
     'ConpherenceController' => 'applications/conpherence/controller/ConpherenceController.php',
     'ConpherenceCreateThreadConduitAPIMethod' => 'applications/conpherence/conduit/ConpherenceCreateThreadConduitAPIMethod.php',
-    'ConpherenceCreateThreadMailReceiver' => 'applications/conpherence/mail/ConpherenceCreateThreadMailReceiver.php',
     'ConpherenceDAO' => 'applications/conpherence/storage/ConpherenceDAO.php',
     'ConpherenceDurableColumnView' => 'applications/conpherence/view/ConpherenceDurableColumnView.php',
     'ConpherenceEditor' => 'applications/conpherence/editor/ConpherenceEditor.php',
@@ -4193,7 +4192,6 @@
     'ConpherenceConstants' => 'Phobject',
     'ConpherenceController' => 'PhabricatorController',
     'ConpherenceCreateThreadConduitAPIMethod' => 'ConpherenceConduitAPIMethod',
-    'ConpherenceCreateThreadMailReceiver' => 'PhabricatorMailReceiver',
     'ConpherenceDAO' => 'PhabricatorLiskDAO',
     'ConpherenceDurableColumnView' => 'AphrontTagView',
     'ConpherenceEditor' => 'PhabricatorApplicationTransactionEditor',
diff --git a/src/applications/conpherence/mail/ConpherenceCreateThreadMailReceiver.php b/src/applications/conpherence/mail/ConpherenceCreateThreadMailReceiver.php
deleted file mode 100644
--- a/src/applications/conpherence/mail/ConpherenceCreateThreadMailReceiver.php
+++ /dev/null
@@ -1,67 +0,0 @@
-<?php
-
-final class ConpherenceCreateThreadMailReceiver
-  extends PhabricatorMailReceiver {
-
-  public function isEnabled() {
-    $app_class = 'PhabricatorConpherenceApplication';
-    return PhabricatorApplication::isClassInstalled($app_class);
-  }
-
-  public function canAcceptMail(PhabricatorMetaMTAReceivedMail $mail) {
-    $usernames = $this->getMailUsernames($mail);
-    if (!$usernames) {
-      return false;
-    }
-
-    $users = $this->loadMailUsers($mail);
-    if (count($users) != count($usernames)) {
-      // At least some of the addresses are not users, so don't accept this as
-      // a new Conpherence thread.
-      return false;
-    }
-
-    return true;
-  }
-
-  private function getMailUsernames(PhabricatorMetaMTAReceivedMail $mail) {
-    $usernames = array();
-    foreach ($mail->getToAddresses() as $to_address) {
-      $address = self::stripMailboxPrefix($to_address);
-      $usernames[] = id(new PhutilEmailAddress($address))->getLocalPart();
-    }
-
-    return array_unique($usernames);
-  }
-
-  private function loadMailUsers(PhabricatorMetaMTAReceivedMail $mail) {
-    $usernames = $this->getMailUsernames($mail);
-    if (!$usernames) {
-      return array();
-    }
-
-    return id(new PhabricatorUser())->loadAllWhere(
-      'username in (%Ls)',
-      $usernames);
-  }
-
-  protected function processReceivedMail(
-    PhabricatorMetaMTAReceivedMail $mail,
-    PhabricatorUser $sender) {
-
-    $users = $this->loadMailUsers($mail);
-    $phids = mpull($users, 'getPHID');
-
-    $conpherence = id(new ConpherenceReplyHandler())
-      ->setMailReceiver(ConpherenceThread::initializeNewRoom($sender))
-      ->setMailAddedParticipantPHIDs($phids)
-      ->setActor($sender)
-      ->setExcludeMailRecipientPHIDs($mail->loadAllRecipientPHIDs())
-      ->processEmail($mail);
-
-    if ($conpherence) {
-      $mail->setRelatedPHID($conpherence->getPHID());
-    }
-  }
-
-}