Checklist for finding out why an account keeps locking out of AD.
- Check event ID’s: 529, 539, 644, 671, 675, 676, 681, 4771, 4625, 4740 2. Scripts
- Credential Manager
- Scheduled tasks
- System Credential Manager (run psexec to open the system user, and check there),
- SQL agent jobs
- 3rd party RDP programs like RDTabs and Terminals.
If none of the above, then turn on AD debug logging, netlogon issues can present themselves in wonky ways.