New Post: Problem to response the xls File to the Client

Thanks for your time MindCore, I find that my problem is not with NPOI, my problem was an error in IE thant does not unsderstand the JSON i have to add a JSCRIPT File the implement the JSON the File "minjson2.js" that implemente the methods JSON.stringify(Objeto) and other that suppose are native in the navigator.

Sorry my english is not very well thanks for your time to advice.