TrojanDownloader:O97M/Xdoc.YA Can't Be Quarantined Or Deleted By Windows Defender

July 25, 2019

My client's Win 10 Pro (version 1903) computer has contracted the despicable TrojanDownloader:O97M/Xdoc.YA trojan from somewhere and I've run multiple scans with Windows Defender (including a couple of Offline Scans) but it continues to report "Remediation incomplete" over and over again. I've also run (the paid premium version of) Malwarebytes as well as Spybot Search & Destroy, all updated with the latest definitions. Crazily enough, they won't even detect the thing, which at least Defender did. The "Help Page" is no help at all, since it assumes that Windows Defender was able to catch and delete the Trojan. I haven't seen one this bad in a long time, mainly because my machines all have the afore-mentioned multi-layered defense, including SpywareBlaster (which I know is a passive, not active measure). Any suggestions would be appreciated...

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