diff --git a/features/language-plugin.feature b/features/language-plugin.feature
index ab2e8693..ab39afc7 100644
--- a/features/language-plugin.feature
+++ b/features/language-plugin.feature
@@ -157,7 +157,7 @@ Feature: Manage translation files for a WordPress install
     When I try `wp language plugin install hello-dolly en_GB de_DE invalid_lang`
     Then STDERR should be:
       """
-      Warning: Language 'invalid_lang' not available.
+      Warning: Language 'invalid_lang' for 'hello-dolly' not available.
       """
     And STDOUT should contain:
       """
diff --git a/features/language-theme.feature b/features/language-theme.feature
index c3b16618..fb28605f 100644
--- a/features/language-theme.feature
+++ b/features/language-theme.feature
@@ -142,7 +142,7 @@ Feature: Manage translation files for a WordPress install
     When I try `wp language theme install twentyten invalid_lang`
     Then STDERR should be:
       """
-      Warning: Language 'invalid_lang' not available.
+      Warning: Language 'invalid_lang' for 'twentyten' not available.
       """
     And STDOUT should be:
       """
diff --git a/src/WP_CLI/CommandWithTranslation.php b/src/WP_CLI/CommandWithTranslation.php
index 1cfcdd33..ca4b2b9e 100644
--- a/src/WP_CLI/CommandWithTranslation.php
+++ b/src/WP_CLI/CommandWithTranslation.php
@@ -216,7 +216,7 @@ protected function download_language_pack( $download, $slug = null ) {
 		}
 
 		if ( ! $translation_to_load ) {
-			return new \WP_Error( 'not_found', "Language '{$download}' not available." );
+			return new \WP_Error( 'not_found', $slug ? "Language '{$download}' for '{$slug}' not available." : "Language '{$download}' not available." );
 		}
 		$translation = (object) $translation;
 
@@ -235,7 +235,7 @@ protected function download_language_pack( $download, $slug = null ) {
 		}
 
 		if ( ! $result ) {
-			return new \WP_Error( 'not_installed', "Could not install language '{$download}'." );
+			return new \WP_Error( 'not_installed', $slug ? "Could not install language '{$download}' for '{$slug}'." : "Could not install language '{$download}'." );
 		}
 
 		return $translation->language;