Configure the quarantine directories on the Microsoft Exchange Server. The quarantine directory will be excluded from scanning.
Quarantine directories are file-based and do not reside on the Information Store.
The Messaging Security Agent quarantines email messages according to configured actions. The following are the quarantine directories:
Antivirus: Quarantines email messages containing virus/malware, spyware/grayware, worms, Trojans, and other malicious threats.
Anti-spam: Quarantines spam and phishing email.
Attachment blocking: Quarantines email messages containing restricted attachments.
Content filtering: Quarantines email messages containing restricted content.
By default, all directories have the same paths (<Messaging Security Agent installation folder>\storage\quarantine). You can change the paths for each or all of the directories.