Kuldeep,

   It sounds like you want to create excel workbooks for versions of excel
prior to 2007 (even though the version before 2007 could handle XML, it
sounds like you don't want that either).  If you are not going to use XML or
interop, then you have to use a third party component to generate the file
(you should be able to google for some).  The format of those files is not
in the public domain, so you are more than likely going to have to pay for
it as well.

ActiveReports from DataDynamics includes an excel writer which we use
to generate Excel files.  We were already using their reporting engine
so there was no cost, so I can't say whether buying ActiveReports just
for the excel writer is worthwhile, but it is an option.

http://www.datadynamics.com

While we're not at all happy with DataDynamics in general, we've found
the excel writer pretty easy to use and the API was straightforward.

Sam

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