I think it gave some conflict with the core of the node-red app itself when I had both node-red dashboard and dashboard-evi and consequently damaged the node-red app itself.
I think that because I read in anothe post around there that dashboard-evi is a fork of the official node-red dashboard.
Another thing is that you must remember, for the time being when I had both files you asked me then the dashboard-evi was unninstalled, may be for that reason can't be seen anything wrong on those files.
Anyway, your suggestion of renaming the .node-red folder and starting node-red again worked well so thank you.
If that had happened then removing the .node-red folder would not have fixed it. You are still using the same node-red app that you were before. It was probably something in your flows that was causing the problem.