Check for Defender definition updates in Windows Update, it should be fine now.
Thanks, AD. I've installed the latest Defender updates as of today. While that may address current and future MC 32 installations, it doesn't seem to be of any help in getting rid of the threat alert in Defender after installing MC 32.0.20 yesterday.
I looked again at the last entry in the Defender log in Event Viewer. The log (after the updated Defender definitions) indicated that Defender had quarantined the trojanscript wacatac.b!ml, but at the end of the entry was an error message reporting that the folder/file couldn't be located.
If JRiver, Defender, Microsoft Safety Scanner, Malwarebytes and Sophos (aka Hitman Pro) all say there's nothin' to see here, folks, I believe 'em.
I'd just really, really like to get rid of the persistent and apparently spurious threat alert, which I can't help but see in the taskbar notification area.