This was the question asked by one of the user in the forums. Precisely the answer is no, as you cannot restore a log or database from SQL 2005 to 2000 version due to the differences in the design. Moreover for the sake of high availability the method of performing Log shipping between 2005 and 2000 instance will not be valid, as in case if you need to restore the database if any issues on primary server then it is not allowed, as you can restore from 2000 to 2005 but not reverse-way. It doesn't...(
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Read the complete post at http://sqlserver-qa.net/blogs/ha/archive/2007/09/27/can-we-do-logshipping-from-sql-2005-to-2000-how-it-is-different-between-2-sql-versions.aspx