So I have a program below which writes an excel file with multiple sheets based on inputs of sheet names, data, cell types, etc. It uses Apache POI, which is currently the only thing I found (correct me if I'm wrong about this) that can write excel 2007 files. The program works. I've tested it out on very small files (I will include the commented out main method that you can use to test this out yourself if you'd like, that is assuming you download...