When opening large executable files like Excel.exe or Outlook.exe, it takes 15 to 20 seconds with Symantec Endpoint Protection (SEP) Application Control installed using SEP 12.1 RU6 (MP5 - MP8), 14.0 (MP1 and MP2). Excel and Outlook have been reported opening slowly using Office 2013, Office 2016 or Office 365.
This performance issue is not specific to Office, Excel.exe or Outlook.exe, this can occur with any large executable (*.exe) file.
When using a high number of hash values in various Application Control (AC) rule sets, AC spends a lot of unnecessary time calculating the checksum value (MD5) when there are matching or duplicate hash values.
This issue is fixed in Symantec Endpoint Protection Client 14 RU1. For information on how to obtain the latest build of Symantec Endpoint Protection, read
TECH 103088: Download the latest version of Symantec Endpoint Protection