|A few things you could try,|
Try opening with a text editor, such as Wordpad or JEdit.
Open a new instance of Excel and turn OFF auto calculation then try to open the corrupt file.
Try Excel in Safe mode:
Type in: Excel.exe /s
you may need to use the complete path to the Excel executable which would be something like:
"C:\Program Files\Microsoft Office\Office\Excel.exe" /s
Then try to open the corrupt file.