What does Windows error code 129 (ERROR_CHILD_NOT_COMPLETE) mean? Status / error code: Category: Constant name: Source: Operating System: Description: The %1 application cannot be run in Win32 mode. Could be also: ConstantTypeOS ENETRESETerrnoSolaris ENOTSUPerrnoWindows SPIN_LOCK_INIT_FAILUREBugCheck CodeWindows Looking for a different code? Search another status or error code.