i have now uninstalled the version ms security ess. 4.1.0522
than cleaned and restarted my pc...installed the new version .... 4.2.223.1 and updated older big 68 MB signature how used in 4.1.0522 and one day later i installed the newest big signature-file - perhaps there are also such " mpcache*.bin " on such degree of dimension...
but luckily
there are no such "mpcache-....bin*" files with summary 100 and more MB.
i think, this blue selected files as in pic 1 can be deleted.