diff -u b/src/Tests/CasUserAdminTest.php b/src/Tests/CasUserAdminTest.php
--- b/src/Tests/CasUserAdminTest.php
+++ b/src/Tests/CasUserAdminTest.php
@@ -29,8 +29,8 @@
 
     // Add a CAS username.
     $cas_name = $this->randomName();
-    $account->set('cas_name', $cas_name);
-    $account->save();
+    $edit['cas_name'] = $cas_name;
+    $account = user_save($account, $edit);
     $this->assertEqual($cas_name, $account->cas_name, t('CAS username %cas_name successfully created.', array('%cas_name' => $cas_name)));
 
     // Reload the account and ensure the CAS name is still present.
diff -u b/src/Tests/CasWebTestBase.php b/src/Tests/CasWebTestBase.php
--- b/src/Tests/CasWebTestBase.php
+++ b/src/Tests/CasWebTestBase.php
@@ -80,8 +80,8 @@
     $this->assertTrue(file_exists($cas_library_dir . '/CAS.php'), t('CAS.php found in @cas_library_dir.', array('@cas_library_dir' => $cas_library_dir)));
 
     // Set the CAS library directory.
-    $config = \Drupal::config('cas.server');
-    $config->set('library_dir', $cas_library_dir);
+    $config = \Drupal::config('cas.settings');
+    $config->set('cas_library_dir', $cas_library_dir);
     $config->save();
   }
 
@@ -107,8 +107,8 @@
     if (empty($cas_name)) {
       $cas_name = $this->randomName();
     }
-    $account->set('cas_name', $cas_name);
-    $account->save();
+    $edit['cas_name'] = $cas_name;
+    $account = user_save($account, $edit);
 
     // Restore password.
     $account->pass_raw = $pass_raw;