In addition to other suggestions, here's one that can give you a bit more useful info:

perl -MSpreadsheet::WriteExcel::Big -wle'print $Spreadsheet::WriteExce
+l::Big::VERSION'
[download]

This tells you if the module is installed - you'll get an obvious, comprehensive error if it's not - as well as showing you the version of the installed module. In other words, if it is installed and you're still having trouble, the version number will help you decide whether you need to update or (if you already have the latest version) if even the latest version doesn't do what you need it to do.