Why won Excel open an .xls file that I received?
The excel file is not opened because it might be the reason that you are using older version of the MS Office and trying to open in a new version of MS Office . In this condition you should use only one version of the MS Office. Or there might also be corruption problem in your MS Excel file so to resolve the problem you can use Repair Excel File. it is the best software that can be used to resolve the problem.
During transferring this file over Internet it could be corrupted, try to use excel 2003 repair
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