When I download an Excel file in xls format from our server I get the warning below in Internet Explorer. The Excel file is generated using Flexcel for .Net using the save method of the XlsFile class:excel.Save(stream, TFileFormats.Xls); The download link ends with the .xls extension but is changed …

Internet explorer changes xsl extension to xlt

Verhoeven_Jan (Verhoeven Jan) February 18, 2012, 11:39am 3

See the following blog page from Microsoft that explains the problem:

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