Is system safe to allow??

Hi there, i am new to the forums so sorry if i am posting in wrong place, about a week ago after updating CIS i started getting a message that system is unrecognized and is trying to modify a something in the system folder. So at firts I blocked it but when I restarted PC I was unable to log in and had to enter safe mode to disable deffence + , so basicaly i want to know if this is a malware or could i just ad it to trusted files? I wish I could atach a more complete log but the old one got to big and got deleted so this is it…
Log:

Date Application Action Target
2011-02-20 17:25:32 System Modify File C:\Windows\System32\LogFiles\HTTPERR\httperr1.log