Index: wp-admin/includes/class-wp-automatic-updater.php
===================================================================
--- wp-admin/includes/class-wp-automatic-updater.php	(revision 48287)
+++ wp-admin/includes/class-wp-automatic-updater.php	(working copy)
@@ -386,7 +386,7 @@
 
 			// Core doesn't output this, so let's append it so we don't get confused.
 			if ( is_wp_error( $upgrade_result ) ) {
-				$skin->error( __( 'Installation Failed' ), $upgrade_result );
+				$skin->error( __( 'Installation failed' ), $upgrade_result );
 			} else {
 				$skin->feedback( __( 'WordPress updated successfully' ) );
 			}
Index: wp-admin/js/updates.js
===================================================================
--- wp-admin/js/updates.js	(revision 48287)
+++ wp-admin/js/updates.js	(working copy)
@@ -727,7 +727,7 @@
 					$button.data( 'name' )
 				)
 			)
-			.text( __( 'Installation Failed!' ) );
+			.text( __( 'Installation failed' ) );
 
 		wp.a11y.speak( errorMessage, 'assertive' );
 
@@ -1364,7 +1364,7 @@
 					$button.data( 'name' )
 				)
 			)
-			.text( __( 'Installation Failed!' ) );
+			.text( __( 'Installation failed' ) );
 
 		wp.a11y.speak( errorMessage, 'assertive' );
 
Index: wp-admin/update-core.php
===================================================================
--- wp-admin/update-core.php	(revision 48287)
+++ wp-admin/update-core.php	(working copy)
@@ -646,7 +646,7 @@
 	if ( is_wp_error( $result ) ) {
 		show_message( $result );
 		if ( 'up_to_date' != $result->get_error_code() && 'locked' != $result->get_error_code() ) {
-			show_message( __( 'Installation Failed' ) );
+			show_message( __( 'Installation failed' ) );
 		}
 		echo '</div>';
 		return;