Search in Exchange Server 2007 (Exchange Search) is completely different from earlier versions of Exchange. Improvements were made to performance, Content Indexing, and Search. New items are indexed almost immediately after their arrival into a mailbox giving end users a fast, reliable, and more stable search function. In Exchange 2000 and Exchange 2003, indexing was not enabled by default. In Exchange 2007, indexing is enabled by default on all mailbox databases and there is no initial setup or configuration required. In Exchange 2007, the indexes’re held in a catalog which is created in the same location as the database files. Extensive research and experience shows that 5-10% of the database size can be expected for the catalog. This’s a great improvement over Exchange 2003 which created a content index that was 35-45% of the database size.
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