diff --git a/src/applications/auth/engine/PhabricatorAuthSessionEngine.php b/src/applications/auth/engine/PhabricatorAuthSessionEngine.php
--- a/src/applications/auth/engine/PhabricatorAuthSessionEngine.php
+++ b/src/applications/auth/engine/PhabricatorAuthSessionEngine.php
@@ -163,6 +163,7 @@
     $user = $user_table->loadFromArray($info);
 
     $user->attachRawCacheData($cache_raw);
+    $user->setAllowInlineCacheGeneration(true);
 
     switch ($session_type) {
       case PhabricatorAuthSession::TYPE_WEB:
diff --git a/src/applications/metamta/query/PhabricatorMetaMTAActorQuery.php b/src/applications/metamta/query/PhabricatorMetaMTAActorQuery.php
--- a/src/applications/metamta/query/PhabricatorMetaMTAActorQuery.php
+++ b/src/applications/metamta/query/PhabricatorMetaMTAActorQuery.php
@@ -59,6 +59,7 @@
     $users = id(new PhabricatorPeopleQuery())
       ->setViewer($this->getViewer())
       ->withPHIDs($phids)
+      ->needUserSettings(true)
       ->execute();
     $users = mpull($users, null, 'getPHID');
 
diff --git a/src/applications/metamta/replyhandler/PhabricatorMailReplyHandler.php b/src/applications/metamta/replyhandler/PhabricatorMailReplyHandler.php
--- a/src/applications/metamta/replyhandler/PhabricatorMailReplyHandler.php
+++ b/src/applications/metamta/replyhandler/PhabricatorMailReplyHandler.php
@@ -337,9 +337,12 @@
 
     $all_phids = array_merge($to, $cc);
     if ($all_phids) {
+      // We need user settings here because we'll check translations later
+      // when generating mail.
       $users = id(new PhabricatorPeopleQuery())
         ->setViewer(PhabricatorUser::getOmnipotentUser())
         ->withPHIDs($all_phids)
+        ->needUserSettings(true)
         ->execute();
       $users = mpull($users, null, 'getPHID');
 
diff --git a/src/applications/people/query/PhabricatorPeopleQuery.php b/src/applications/people/query/PhabricatorPeopleQuery.php
--- a/src/applications/people/query/PhabricatorPeopleQuery.php
+++ b/src/applications/people/query/PhabricatorPeopleQuery.php
@@ -528,9 +528,6 @@
     $cache_data = igroup($cache_data, 'userPHID');
     foreach ($user_map as $user_phid => $user) {
       $raw_rows = idx($cache_data, $user_phid, array());
-      if (!$raw_rows) {
-        continue;
-      }
       $raw_data = ipull($raw_rows, 'cacheData', 'cacheKey');
 
       foreach ($keys as $key) {
diff --git a/src/applications/people/storage/PhabricatorUser.php b/src/applications/people/storage/PhabricatorUser.php
--- a/src/applications/people/storage/PhabricatorUser.php
+++ b/src/applications/people/storage/PhabricatorUser.php
@@ -65,6 +65,7 @@
 
   private $settingCacheKeys = array();
   private $settingCache = array();
+  private $allowInlineCacheGeneration;
 
   protected function readField($field) {
     switch ($field) {
@@ -483,7 +484,11 @@
     }
 
     $settings_key = PhabricatorUserPreferencesCacheType::KEY_PREFERENCES;
-    $settings = $this->requireCacheData($settings_key);
+    if ($this->getPHID()) {
+      $settings = $this->requireCacheData($settings_key);
+    } else {
+      $settings = array();
+    }
 
     $defaults = PhabricatorSetting::getAllEnabledSettings($this);
 
@@ -1486,6 +1491,10 @@
     return $this;
   }
 
+  public function setAllowInlineCacheGeneration($allow_cache_generation) {
+    $this->allowInlineCacheGeneration = $allow_cache_generation;
+    return $this;
+  }
 
   /**
    * @task cache
@@ -1506,6 +1515,12 @@
       return $usable_value;
     }
 
+    // By default, we throw if a cache isn't available. This is consistent
+    // with the standard `needX()` + `attachX()` + `getX()` interaction.
+    if (!$this->allowInlineCacheGeneration) {
+      throw new PhabricatorDataNotAttachedException($this);
+    }
+
     $usable_value = $type->getDefaultValue();
 
     $user_phid = $this->getPHID();
diff --git a/src/infrastructure/testing/PhabricatorTestCase.php b/src/infrastructure/testing/PhabricatorTestCase.php
--- a/src/infrastructure/testing/PhabricatorTestCase.php
+++ b/src/infrastructure/testing/PhabricatorTestCase.php
@@ -202,6 +202,14 @@
     $editor->setActor($user);
     $editor->createNewUser($user, $email);
 
+    // When creating a new test user, we prefill their setting cache as empty.
+    // This is a little more efficient than doing a query to load the empty
+    // settings.
+    $user->attachRawCacheData(
+      array(
+        PhabricatorUserPreferencesCacheType::KEY_PREFERENCES => '[]',
+      ));
+
     return $user;
   }