This article applies to Barracuda PST Enterprise version 3.2 and higher
PST Enterprise supports deduplication when migrating messages to the PST owner's Exchange primary or archive mailbox. This deduplication only applies to IPM.Note and IPM.Post message classes.
- PST Enterprise Compares the message's PR_SEARCH_KEY property value with that of all the messages in the destination folder in the mailbox.
- Deduplication only occurs for duplicate messages within the same folder, not for duplicate messages located in elsewhere in the mailbox.
- First the PR_SEARCH_KEY is compared. The PR_SEARCH_KEY is a property which contains an Exchange identifier unique to the message, but does not change if the message is copied or modified. This means that, for example, two messages created at different times but with identical subjects are not considered duplicates due to different PR_SEARCH_KEY values.
- If another message is found with the same PR_SEARCH_KEY value, the following properties are compared:
- Body text
- Last verb applied, for example, replied/forwarded, and its time
- Read/unread status
- Code page (character set)
- The binary content of any attachments
- If there are any embedded messages, the same algorithm is applied to all of those messages
If all the properties in the preceding list are identical, the message is considered a duplicate and deleted rather than migrated. If any of the above properties differ, the message is considered unique and migrated.
- In the audit CSV file this is reported as: "Message compared to user's mailbox, found to be duplicate so deleted"
- In the Last Status Update in the administration website, this is reported similar to: "Migrated 9 messages out of 15 that matched from 15 found. 6 messages deleted due to being duplicate"