You cannot restore or attach a 2005 database to 2000, 2005 added stuff to the database file formats
that wasn't known when MS wrote 2000 (obviously). To downgrade, you have to go the script,
export/import route (using BCP, DTS, SSIS etc).
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Tibor Karaszi, SQL Server MVP
http://www.yqcomputer.com/
http://www.yqcomputer.com/