Light silent mode turned off status completed x2 ?????

Hi Guys

I found this in my recent history logs this morning,when I went to click the more details button it was grayed out??? Any Ideas what this means.The silent mode is on its default setting which is off.Is it the same thing?Earlier in the morning in Norton tamper protection there was windows\system32\mrt.exe at a medium risk,I have just installed Malwarebytes is that part of it.I know full of questions.

NIS2009 XP SP3

Cheers Mo