I've recently upgraded from V9.8.1 to 10.4.2. Once deployed, I've found that my users who have some very old databases (older than June, 2016) can't open those databases. I don't know the version of Valentina that made them for sure, but I think 5.8.8. I *can* open them if I revert to 9.8.1.
I didn't see anything about loss of backward compatibility, so my question is, is this expected? If so that's OK, but if not I'll file a Mantis report.