CAT12: Error Creating Link - Access is Denied

Francois · December 6, 2021, 10:08am

The error message "Access is denied" is returned by Windows when Brainstorm tries using the command "mklink /D" to create a link from the SPM12 toolbox folder $HOME/.brainstorm/plugins/spm12/spm12/toolbox/cat12 to the CAT12 installation folder $HOME/.brainstorm/plugins/cat12/cat12.

github.com

brainstorm-tools/brainstorm3/blob/master/toolbox/core/bst_plugin.m#L2239


        end
        % Define source and target for the link
        if ~isempty(PlugCat.SubFolder)
            linkTarget = bst_fullfile(PlugCat.Path, PlugCat.SubFolder);
        else
            linkTarget = PlugCat.Path;
        end
        linkFile = spmCatDir;
        % Create link
        if ispc
            linkCall = ['mklink /D "' linkFile '" "' linkTarget '"'];
        else
            linkCall = ['ln -s "' linkTarget '" "' linkFile '"'];
        end
        disp(['BST> Creating symbolic link: ' linkCall]);
        [status,result] = system(linkCall);
        if (status ~= 0)
            error(['Error creating link: ' result]);
        end
    end
end

This is most likely a problem of access rights of your user.
Access rights issues on Windows 7 or 10 are sometimes difficult to identify and fix...

Try running Matlab as administrator
Check the access rights of all the subfolders of the .brainstorm folder
Make sure your user has the rights to create symbolic links

Workaround:
If you can't figure out a solution:

Uninstall the CAT12 and SPM12 plugin from Brainstorm,
Download and install them manually on your computer (not in any of the Brainstorm folders), with CAT12 really located in the SPM12 toolbox folder,
Configure Brainstorm to use these custom installations for the two plugins, with the menu "Custom install": https://neuroimage.usc.edu/brainstorm/Tutorials/Plugins#Example:_FieldTrip