I'd suggest to read this:
Accessing Microsoft Office Data from .NET Applications[
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If Excel sheet contains headers, use sql query as below:
SELECT [HeaderName1], [HeaderName2], [HeaderName3]
FROM [SheetName$]
If not:
SELECT [1], [2], [3]
FROM [SheetName$]
Note, you need to set proper connection string in both cases:
http://www.connectionstrings.com/excel/[
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