Exporting project information to excel pivot table and workbook

I am new to Microsoft Project 2007. When I opened a project today and then entered some task information in a new file, then I didnt copy for anywhere. So after that I tried to use the file to save as excel pivot table but then got some kind of error that says "You are trying to save a file saved in an older file format. Your settings do not allow you to save the file in older file formats. To change your setting, navigate to the "Security" tab in the Options dialog box." Can anyone tell me how to solve this error? Thanks.

I can easily save the Project 2007 files as Excel files without any problems. The settings that I am using for legacy formats is "Allow loading files with legacy or non default file formats." The .xls setting is an older version and not the 2007 version of Excel, so you could be having that kind of an issue. Have you tried changing the setting in Tools >> Options and then Security? Check that and let us know whether it worked for you or not.

I am using the Excel 2007 and I have changed the settings that you have suggested me and now everything is working fine. Thanks a bunch for your help.

I am glad that you have sorted out the problem, and thanks for the feedback.