Wizard of X

I ran into a problem that it took me a few hours to figure out, so maybe I can spare someone the headache. I'm creating a file using POI and streaming it to the browser. It was working great in Firefox, but in Internet explorer if I opened the file instead of saving it, the file name was xAgent_PrintForm.xsp and not the correct Form.docx . If I saved the file, it had the correct file name. Even worse, it had been working fine before and just started happening without any explanation. It turned out to be a header in my response writer.