The default retention period for messages in Microsoft Defender Quarantine is 30 days. After this period, the messages are automatically deleted.

Quarantine: Holds messages that are considered potentially dangerous or highly suspicious. These messages have been identified by Microsoft Defender as containing malware, phishing attempts, or other significant threats. Access to quarantine might be more restricted, and notifications are often sent about quarantined items. Junk Email Folder: Contains messages that are identified as spam or unsolicited bulk email. While these can be annoying, they are generally not considered actively harmful. These messages are usually moved directly to your Junk Email folder in your email client.

Yes, Microsoft Defender Quarantine is already enabled for your email, and you don't need to manually enable it. Your IT administrators configure and manage these security features.

Microsoft Defender Quarantine is a feature that holds potentially harmful or suspicious email messages that have been filtered out by Microsoft's security systems. This prevents these messages from reaching your inbox, protecting you from potential threats like malware, phishing attempts, and spam.