I think I've figured out a partial solution. I took a guess at which design study might be at issue (i assumed it was part of the last oe I had open) and moved that folder (apparently 71Gb of my 90Gb) out and opened the CFDST. That seemed to work, it doesn't crash now. I had tried using the support CFZ and that still crashed. So apparently one of the scenarios within that study is bad. One is 20Gb the other 50Gb. I don't know why whese are so large, they were supposed to be MUCH less iterations and elements than all my other scenarios that average about 10Gb. So my immediate issue is resolved. *whew*