You might see a blue screen error after you install or upgrade to the ENS Threat Prevention 10.7.0 February 2021 Update and later. The Bug check code can be Bug check 3b, Bug check 19, Bug check 50, or Bug check 5d. This issue is random and only occurs in a few environments. There have been certain cases wherein when the driver verifier has been enabled on the system, the blue screen error doesn't occur anymore.
First example of a stack trace:
ffffd001`686e4720 fffff800`f6cce175 : 00000000`0000032c 00000000`00000e28 ffffe801`86003b30 fffff800`f6d70090 : mfehidk!
ffffd001`686e4750 fffff800`f6cd302c : 00000000`00000000 00000000`00000e28 00000000`00000e28 00000000`00000e01 : mfehidk!
ffffd001`686e47b0 fffff800`f6c94ac7 : 00000000`00000000 ffffe801`86374080 ffffe001`b4579670 ffffe001`ade17848 : mfehidk!
ffffd001`686e4830 fffff800`f6c94c97 : ffffe001`b482de00 00000000`00000e28 ffffe801`86374080 ffffe001`ade177e0 : mfehidk!
ffffd001`686e4860 fffff803`5c6437cd : ffffe801`86374080 fffff803`5c553b20 00000000`00000001 ffffe801`86374080 : mfehidk!
Second example of a stack trace, for the process
mcshield.exe:
ffffd000`21cdad28 fffff802`6caa7156 : 00000000`00000019 00000000`0000000e ffffe000`cae5b110 00730061`006c0063 : nt!KeBugCheckEx
ffffd000`21cdad30 fffff801`ae5303a8 : ffffd000`21cdaf00 00000000`00000000 00000000`00000000 00000000`00000000 : nt!ExDeferredFreePool+0x746
ffffd000`21cdae00 fffff801`ae51c11f : ffffe000`c694c230 00000000`00000000 ffffc000`7026c780 ffffe000`00000000 : mfencbdc+0x673a8
ffffd000`21cdae30 fffff801`ae51bf6b : 00000000`00000000 ffffe000`cbaf41e2 ffffd000`21cdb000 ffffe000`cbaf4190 : mfencbdc+0x5311f
ffffd000`21cdaed0 fffff801`ae51cfb6 : 00000000`00000000 ffffe000`cbaf41fa ffffe000`c7e071f0 00000000`0000007c : mfencbdc+0x52f6b
ffffd000`21cdaf50 fffff801`ae4d181b : ffffe000`c86fca80 ffffe000`c7e071f0 ffffe000`cbaf4180 00000000`c000a3d0 : mfencbdc+0x53fb6
ffffd000`21cdaf90 fffff801`ae5346da : 00000000`00000000 00000000`00000000 ffffe000`c86fcb50 00000000`00000000 : mfencbdc+0x881b
ffffd000`21cdb010 fffff802`6cc9bdff : 00000000`00000002 ffffd000`21cdb111 ffffe000`c7e071f0 ffffe000`c7bd6900 : mfencbdc+0x6b6da