Unfortunately it is not clear what has gone wrong, as this error
MURAT wrote
Error using figure: uIcontrolfontunits is an invalid class name
does not really tell anything about what or where the issue could be. You can possibly try with another Matlab version (or check with the Mathworks about this error). Or you could try and see if starting FEATool manually helps, to do this follow the steps below:
1. Download the archive for the latest release from
https://github.com/precise-simulation/featool-multiphysics/releases/latest2. Unpack/unzip it to a folder on your computer (note this folder as
path_to_featool_multiphysics_folder).
3. (Re-)start Matlab.
4. Run the following commands in the Matlab terminal (substitute
path_to_featool_multiphysics_folder with the actual path to where you have downloaded and extracted the FEATool distribution).
>> cd path_to_featool_multiphysics_folder
>> featool
Moreover, you can test to check if it is a pure GUI issue or overall installation issue my running the test suite without the GUI (only running the m-script file models). To do this launch the FEATool test suite as
>> featool testm