Oftentimes, it is an error with the import wizard. Try repairing your Office
installation.
Othertimes, it's a problem with the spreadsheet file -- path string is too
long, invalid extension (not an .xls or other EXCEL extension), etc.
You'll need to give us more information about how you're doing the import
(using File | Get External Data | Import ? or using TransferSpreadsheet in
VBA or macro ?), the details about the EXCEL file's path and filename, etc.