diff --git a/core/modules/aggregator/aggregator.install b/core/modules/aggregator/aggregator.install
index e236628953d587b43b8566b18106246db619c880..cd7203f17d15e47fce14b1851a96f56ba679f7cd 100644
--- a/core/modules/aggregator/aggregator.install
+++ b/core/modules/aggregator/aggregator.install
@@ -17,7 +17,7 @@ function aggregator_requirements($phase) {
   );
   if (!$has_curl) {
     $requirements['curl']['severity'] = REQUIREMENT_ERROR;
-    $requirements['curl']['description'] = t('The Aggregator module could not be installed because the PHP <a href="http://php.net/manual/curl.setup.php">cURL</a> library is not available.');
+    $requirements['curl']['description'] = t('The Aggregator module requires the <a href="https://secure.php.net/manual/en/curl.setup.php">PHP cURL library</a>. For more information, see the <a href="https://www.drupal.org/requirements/php/curl">online information on installing the PHP cURL extension</a>.');
   }
   return $requirements;
 }
diff --git a/core/modules/simpletest/simpletest.install b/core/modules/simpletest/simpletest.install
index 0e3cd00d5fc09d904437471ddd2254ea8ff11837..9b3ad90b01b6c34df85611664a32cae85c86029f 100644
--- a/core/modules/simpletest/simpletest.install
+++ b/core/modules/simpletest/simpletest.install
@@ -37,7 +37,7 @@ function simpletest_requirements($phase) {
   );
   if (!$has_curl) {
     $requirements['curl']['severity'] = REQUIREMENT_ERROR;
-    $requirements['curl']['description'] = t('The testing framework could not be installed because the PHP <a href="http://php.net/manual/curl.setup.php">cURL</a> library is not available.');
+    $requirements['curl']['description'] = t('The testing framework requires the <a href="https://secure.php.net/manual/en/curl.setup.php">PHP cURL library</a>. For more information, see the <a href="https://www.drupal.org/requirements/php/curl">online information on installing the PHP cURL extension</a>.');
   }
 
   // SimpleTest currently needs 2 cURL options which are incompatible with