@NM ，For your questions, here are my answers for the reference:
Q1. How to find which are the KB's which are installed as part of quality and feature updates ?
A1: In fact, Windows Update Ring policies only define an update strategy (e.g. block driver installation, set deferral period, set maintenance time, etc.), they don’t actually provide the update infrastructure itself. Think of it as being analogous to certain Group Policies for Windows Update deployed from your on-premises Active Directory. This means that you still need to use your existing update solution such as Windows Update or WSUS to obtain the actual updates. To check the hotfix installed on the device, we can use get-hotfix.
Q2. Some of the devices the "update status" shows as failed. For these devices how can we find the reason of failure ? There's nothing that intune console shows.
A2: We can firstly check if the policy has deployed to the device successfully by the methods in the following link:
If the policy is applied successfully, but the update is failed to install. We suggest to contact windows team to check the windows update issue:
Hope it can help.
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