A task with no due-date is stored in the system as the year 0, so using the advanced search, in the due-date range leave the left side blank and put a really old date in the right side, like Jan 1, 1800.
Essentially you are looking for all tasks with a due-date prior to 1800.
After explaining this, I realize that this is totally non-intuitive, so I will add this to our to-do list to fix.
Actually, that <u>is</u> pretty intuitive, and is what I tried to do. The system will not accept a date earlier, however, than the popup calendar dates, which only go back to 2007, and I end up with ALL items returned, I believe.
Hmm, yeah you are right. I should have checked that before typing my (incorrect) response. I'll put this on our todo list to fix. In the meantime, hopefully the "no due-date" tab in the Due-Date view will work.