@Lam, Xin Le Thank you for reaching out to us, As I understand you are looking for details on AIP Unified labelling client/registry details.
we recommend you use you labeling that's built into Office apps, even if you have the Azure Information Protection (AIP) unified labeling client installed. The AIP add-in is now disabled by default in the latest versions of Office apps.
Also refer to this blog for more details - https://techcommunity.microsoft.com/t5/security-compliance-and-identity/retirement-notification-for-the-azure-information-protection/ba-p/3791908
Any specific registry settings you are looking for AIP UL client, I came across this - https://learn.microsoft.com/en-us/microsoft-365/troubleshoot/sensitivity-labels/sensitivity-labels-missing
AIP client uses the registry from the below path HKEY_CURRENT_USER\SOFTWARE\Microsoft\MSIP\ - https://learn.microsoft.com/en-us/azure/information-protection/rms-client/clientv2-admin-guide-customizations#change-the-local-logging-level
Let me know if you have any further questions, feel free to post back.
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