Do you have actually write permission on the directory you want to write to? In your screenshoot there is the message "Failed to open file ..." and this means that opening the file for writing fails. yeah I thin I do have .At least I did chmod ./<dir_name> -R 777.Where else I can have pro...

this is the paste OS: Ubuntu Core 20 (ubuntu:GNOME/ubuntu) Word size of OS: 64-bit Word size of FreeCAD: 64-bit Version: 0.19.24276 (Git) Build type: Unknown Branch: releases/FreeCAD-0-19 Hash: a88db11e0a908f6e38f92bfc5187b13ebe470438 Python version: 3.8.5 Qt version: 5.12.8 Coin version: 4.0.0 OCC ...

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When I try to save my project i get unknown File exception happened and I am unable to save my project

Is there a way to calculate the Aerodynamics of a object(drag ,lift stability etc)?