Hello @Work_account,
would usually say “Welcome to KNIME community!” on your first post but it’s not easy when dealing with such a problem. Sry to hear about this. Losing hours and hours of work is terrible and frustrating. I personally never experienced such problems but have seen this corruption issue over the years. And usually this doesn’t have a same root cause nor solution if one is found at all. Doing backup is definitely something I always recommend. However doing it every day manually (if you are only working with KNIME Analytics Platform) is time consuming and one can easily forget. For example I do it on a monthly basis.
Maybe you can check this topic/workflow solution for workflow backup developed by @mwiegand:
Do You Even Backup? Knime Workspace Backup Workflow v2.1 is Here!
Haven’t tried it (yet!) and not sure if this is the post in regards to latest version but if any questions I’m sure Mike will jump in.
Br,
Ivan