Event Log Structure ( .evtx Files)

• Format: Modern Windows event logs (.evtx files) use a proprietary binary XML-based format. This format allows for structured logging and efficient storage.

• Channels: Windows organizes events into different logs, known as channels, based on their source or purpose. Key channels frequently examined during screenshares include:

  • Application: Contains events logged by various installed applications (non-OS specific). Error reporting often appears here.

  • Security: Records security-related events based on the system's audit policy settings. This includes login attempts (success/failure), account management actions, object access (if enabled), policy changes, and importantly, log clearing events (Event ID 1102). Accessing this log often requires administrator privileges.

  • System: Logs events generated by Windows system components themselves. This includes service start/stop events, driver loading issues, hardware errors, and system time changes (Event ID 4616), and non-security log clearing (Event ID 104).

  • Setup: Records events related to the installation and setup of applications and Windows updates.

  • ForwardedEvents: Used in enterprise environments to collect events forwarded from other computers.

  • Applications and Services Logs: A broader category containing numerous specific logs for individual applications, services, or Windows features (e.g., Microsoft-Windows-TaskScheduler/Operational, Microsoft-Windows-PowerShell/Operational, Microsoft-Windows-Ntfs/Operational for USN Journal deletion). Navigating these requires knowing which specific log might contain relevant information.