Mozilla/5.0 (X11; U; SunOS i86pc; en-US; rv:1.9.1.2) Gecko/20090817 Firefox/3.5.2 Steps to reproduce: 1. Download any file in FF, e.g.: http://dlc.sun.com/osol/opensolaris/2008/11/osol-0811.iso 2. Pause it and then resume it Actual result: The download can be paused, but can not be resumed.A download error appear: /export/home/work/Downloads/osol-0811.iso.part could not be saved, because the source file could not be read. Try again later,or contact the server administrator. Expected result: The download can be resumed without any error

The issue can be reproduced on: Mozilla/5.0 (Windows; U; Windows NT5.1; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2

The server provides a unique hash for each download e.g. http://dlc-cdn-rd.sun.com/c1/osol/opensolaris/2008/11/osol-0811.iso?e=1250742992&h=4790e433ef49450fbe2348b3b085fc1b This can be seen by right clicking on the file in the download manager and choosing copy download link or using wget -S --spider URI. Pausing works for me using a different server http://ftp.osuosl.org/pub/slackware-iso/slackware-12.2-iso/slackware-12.2-install-d1.iso

The server is now gone, this is a very old bug and comment#2 sounds like this was invalid (different hash for each download)