Windows Defender will soon require a newer platform version to support future versions of the antimalware engine.
Download the latest Windows Defender platform to maintain the best level of protection available. The Windows Defender client encountered an error when using the Dynamic Signature Service to download the latest definitions to a specific threat.
This event is usually due to an interruption in network connectivity during an update.
To troubleshoot this event: The Windows Defender client attempted to download and install the latest definitions file and failed.
When the log is full, the file is copied to a file of the same name but with the .lo_ extension, and the process or component continues to write to the file.
Most processes in Configuration Manager write operational information to a log file that is dedicated to that process.
The log files are identified by or .lo_ file extensions.
For those, we specifically call them as Action Time or Detection Time.
Time: The time when the event occurred, for example when the history is purged.