I have had MSE for years and I am aware that the definitions updates come in through Optional Windows Update and get automatically installed. Mostly daily and they are small in size. A new engine is a larger download, but that is always identified in Windows Update as a new engine. Over the past month I have seen phantom downloads of various download size, but I do not know what they are. Lat week it was 29MB, today 58.3MB. One download was over 100MB but there is no indication on the MSE/about tab as to what these downloads are. They come in under Microsoft Security Client MsMpEng exe or MpCmdrun exe. I assume these 2 execs are only for MSE and not other windows update security downloads. Has anyone seen these downloads and do you know what they are?