diff --git a/headers/os/support/Errors.h b/headers/os/support/Errors.h
index c2d88a006d..557d0a128e 100644
--- a/headers/os/support/Errors.h
+++ b/headers/os/support/Errors.h
@@ -106,7 +106,9 @@ enum
 	B_LAUNCH_FAILED_NO_PREFERRED_APP,
 	B_LAUNCH_FAILED_FILES_APP_NOT_FOUND,
 	B_BAD_MIME_SNIFFER_RULE,
-	B_NOT_A_MESSAGE
+	B_NOT_A_MESSAGE,
+	B_SHUTDOWN_CANCELLED,
+	B_SHUTTING_DOWN
 };
 
 
diff --git a/src/system/libroot/posix/string/strerror.c b/src/system/libroot/posix/string/strerror.c
index b5f18a145f..d26cd9ef3d 100644
--- a/src/system/libroot/posix/string/strerror.c
+++ b/src/system/libroot/posix/string/strerror.c
@@ -168,6 +168,10 @@ error_description(int error)
 			return "Bad sniffer rule";
 		case B_NOT_A_MESSAGE:
 			return "Data is not a message";
+		case B_SHUTDOWN_CANCELLED:
+			return "System shutdown cancelled";
+		case B_SHUTTING_DOWN:
+			return "System shutting down";
 
 		// Storage Kit Errors