If you receive a 1501 error. There may be two reasons. The event log file could not be found. The event log file is marked as read-only and stored in%systemroot%/system32/configIt is named AppEvent.evt, SecEvent.evt and SysEvent. Evt, wait. If you lose any files, you can try to copy them from another computer. In addition, you need to check whether these files are writable.