Difference between HotfixID(Installed Windows Patches Information) and Source ID of a patch

Hello

Can someone help me to find an explanation for this behaviour?

I found that the patch with Source ID KB4576750 was not relevant for some servers, to remedy the situation, I created two copies of the same patch. Copy C1 is without the reboot test at the relevance test level, copy C2 is without the boot test and without the registry key verification : HKLM\ \Software\Windows\CurrentVersion\Component Based Servicing\Version. For the C2 copy all Windows 2016 servers in the park are relevant.

I applied the C2 patch on one of the servers that was not relevant at the beginning. The patch was applied well and I see that the server became irrelevant only in regard to copy C1. For C2 it is still irrelevant. For the original patch, the server is still not visible (normal).
At the Computer level and when I check the hostID, I find that the patch is well installed.

My question, why is the C2 patch still relevant for ?

I did another test by installing another KB (month of September) using WSUS, the patch was installed. At bigfix and hotfix level the KB is well installed but on the patch corresponding to this KB the situation is the following (by making like the first example two copies of the patch)

The original version of the patch The server is not visible, normal problem of relevance.
CC1 copy of the patch The server is not visible, normal relevance problem
The CC2 copy of the patch The server remains relevant despite the fact that the patch is installed outside bigfix (checking the HotfixID parameter of the computer shows that the KB is well installed).

As we are in the process of migrating from WSUS to BigFix, the client is validating the reports that have been uploaded by both platforms. I can’t explain the fact that a hotfix is installed and the corresponding patch is not always installed (the copy).

Best Regard

Sorry, I found this a bit confusing to follow. Maybe restructuring the explanation would help lessen my confusion. However, I’ll try to address some points, assuming I understand those points correctly.

For C2, which I’m assuming is a copy of the fixlet where you removed the relevance check for “Component Based Servicing\Version”, I would expect it(C2) to still be relevant after you apply the update and reboot because you have effectively removed the relevance check that determines whether KB4576750 (a Servicing Stack Update) is installed.

If the original fixlet for KB4576750 in the Patches for Windows site is not relevant and you think it should be, the first thing to do would be to evaluate the relevance on the endpoint using Fixlet Debugger (https://developer.bigfix.com/tools/fixlet_debugger.html) to determine which relevance statement is evaluating to False.