"What troubles did you get when recompile with DBProEx ?"
It just didn't work reliably & crashed regularly. It would be a massive job to start debugging with 9EX. I can't stress how much of a huge undertaking it would be since the app works on large databases that could be corrupted in subtle ways. 9EX is great work and I would use it if I was starting on something new. Living with the existing known faults is preferable
"Do you use user defined types that get deleted while containing strings? Some kind of "free string" command is only thing I remember language-based that was needed as a workaround for memory problems.
Maybe undim also had trouble, I'm not sure."
Thanks, I do undim & redimm one UDT but only in a module in the app that very rarely gets used so fairly sure that's not contributing to the leak.