Quick version: New computer, attached to Windows domain, with SteadyState w/ Disk Protection turned on, cannot log on as domain user because Windows states 'system security log is full'

Troubleshooting performed: disabled all 'restrictions' listed in SteadyState, cleared system security log, changed security log settings to overwrite entries when it becomes full, restarted computer to commit changes, verified changes were commited - still cannot log on as domain user, changed Documents and Settings folder to another partition, still cannot log on as domain user

Let me know if you need a more detailed description of any steps performed. I appreciate any help you can give me.