It seems that you are experiencing an issue with the protection history in Windows 11 Pro not deleting as expected, even after adjusting the settings. This could be related to the configuration of the Microsoft Defender Antivirus settings.
One possible reason for this behavior could be that the "Scan_PurgeItemsAfterDelay" policy setting, which defines the number of days items should be kept in the scan history folder before being permanently removed, is not functioning as intended. If this setting is not configured properly, it might prevent the automatic deletion of items in the protection history.
Additionally, if there are any Group Policy settings or third-party applications that manage these configurations, they could override your settings. It may be worth checking if any such configurations exist on your system.
If the issue persists, you may want to consider reaching out to Microsoft Support for further assistance, as it could be a software-related problem specific to your installation of Windows 11 Pro.
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