I am in Albuquerque right now on business, ready to fly home tomorrow. :) To add to the excellent answer from Paul, the only way you can import Excel spreadsheet data into Microsoft Project is if you set up the Excel workbook correctly.
Therefore, I would suggest you try the following:
1. Open any existing Microsoft Project 2010 project file.
2. Click File > Save As.
3. Click the Save As Type pick list and select the Excel Workbook (*.xlsx) file format.
4. Navigate to the folder where you want to save the Excel workbook and then click the Save button.
5. In the Export Wizard dialog, click the Next button.
6. Choose the Project Excel Template option and then click the Finish button.
Launch your Microsoft Excel application and navigate to the folder where you saved the project file as an Excel workbook. Open the Excel workbook and widen all of the columns on each worksheet page. Carefully study how Microsoft Project 2010
exports data to Excel in the Task_Table worksheet, the Resource_Table worksheet, and the Assignment_Table worksheet. You will need to set up your Excel workbook in a very similar manner in order to successfully import data into Microsoft Project.
Hope this helps.
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