I’ve been stumped in a similar manner too. Was working with adding new references to a library consisting of lots of groups in group sets. Closed down for the night, and when I try to open it today I find all my groups and original references just fine, but the entire group set structure is simply gone and I’m left with a long list of ‘unfiled groups’.
Anyone got any idea as to what’s happened with my group sets?
I’m working in X9.3.3.
AA