Hi Nick, I'm sure others on this list will have excellent information for you, but the ftp site for ascend is still up at Lucent, ie: ftp://ftp.ascend.com/pub/Software-Releases/Max/ The OS and the documentation should be there. I believe you require a maintenance contract for the newer releases. The last release I have used for the 6000 was "SW +8.0-133.0+". This has been very stable for us for years. If you look in Screen 00-100 on the main display, you will see the options enabled on your units. Hope this helps...Ed Nick Bright wrote: >I've got quite a few MAX-4000 and several MAX-6000 units, bought off >of eBay. I'm curious if it is possible to obtain updated software for >them? I also have no idea what features are supported by what versions >of the OS. > >