My Phaser 4510DT is still on the original firmware v3.3.0 dated 12/22/2006. It recently developed an issue where it won't print because of low toner even after installing a new cartridge. I'm trying to update to 4.11.2, but when I follow the instructions to send the file to the printer, nothing happens. It just says 'sending request' forever without timing out or generating an error message. The only way I was able to find this firmware version was through a random link posted on a thread in the forum, so if there's another version I need to install first, I can't find it.