I use MBAM free as a standalone (with the update/scan on schedule in background in the newest version) (no real-time protection enabled) and no other 3rd party AV products (no unused/un-activated old trial pre-installed or accidentally installed products either, (check your apps list in either Win 10 settings or in the old familiar Control panel to uninstall if any are shown there) without issue/no conflicts with the Windows Defender suite of protection.
The MBAM currently on my device is as follows:
MBAM version
3.7.1.2839
Package version
1.0.563
Update Package version
1.0.10180
My system is Win 10 Pro build# 17763.437
A comprehensive list of 3rd party AV product full uninstall utility apps (from their respective vendors/creators) can be found at the links below, if needed/wanted:
https://support.eset.com/kb146/?&page=content&id=SOLN146
-Richard
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