You notice large files with extension .2 in the Windows temporary folder.
When the traffic or security logs reaches the maximum size limit the Endpoint Protection client will create a temporary file containing the log in the temporary folder. If the log file has become corrupt this could lead to content being written several times leading to large files.
This issue is fixed in Symantec Endpoint Protection 14.2 RU2. For information on how to obtain the latest build of Symantec Endpoint Protection, see Download the latest version of Symantec software here.