I have been getting a text box when I try to download some Autocad files sent to me from clients for my work. This has recently started, about 5 months ago, and requires me to have them create a zip file to send to me. It is a little frustrating, because with some clients I have to ask again and again where previously there was never a problem. My work computer is not connected to the internet, and my internet connected computer does not have autocad loaded on it. The text box says 'You have chosen to open: Untitled which is: invalid/octed-stream (857KB) from https://dl-mail.ymail.com Is there a switch or setting that I can use to keep this from happening? Did Mozilla change something in the files that you can download and are now only able to download files that have a program on your computer to read/open them?