diff --git a/matlab/CalcNF2FF.m b/matlab/CalcNF2FF.m
index b4123d0..e5868ae 100644
--- a/matlab/CalcNF2FF.m
+++ b/matlab/CalcNF2FF.m
@@ -85,7 +85,15 @@ struct_2_xml(nf2ff.xml,nf2ff_xml,'nf2ff');
 
 m_filename = mfilename('fullpath');
 dir_name = fileparts( m_filename );
-openEMS_Path = [dir_name filesep '..' filesep];
+
+if isunix
+    % <openEMS-path> could be /usr or ~/opt/openEMS etc.
+    % assume this file to be in  '<openEMS-path>/share/openEMS/matlab/'
+    % assume openEMS binary to be in '<openEMS-path>/bin'
+    openEMS_Path = [dir_name filesep '../../../bin' filesep];
+else
+    openEMS_Path = [dir_name filesep '..' filesep];
+end
 
 if ((exist(nf2ff.hdf5,'file') && (mode==0)) || (mode==2))
     disp('CalcNF2FF: Reading nf2ff data only...')
@@ -104,7 +112,7 @@ cd(Sim_Path);
 try
     if isunix
         % remove LD_LIBRARY_PATH set by matlab
-        system(['export LD_LIBRARY_PATH=; ' openEMS_Path 'nf2ff/nf2ff ' filename '.xml']);
+        system(['export LD_LIBRARY_PATH=; ' openEMS_Path 'nf2ff ' filename '.xml']);
     else
         system([openEMS_Path 'nf2ff.exe ' filename '.xml']);
     end
diff --git a/matlab/private/invoke_openEMS.m b/matlab/private/invoke_openEMS.m
index 48a62c8..24bba3f 100644
--- a/matlab/private/invoke_openEMS.m
+++ b/matlab/private/invoke_openEMS.m
@@ -31,11 +31,15 @@ end
 
 filename = mfilename('fullpath');
 dir = fileparts( filename );
-openEMS_Path = [dir filesep '../..' filesep];
 
 if isunix
+    % <openEMS-path> could be /usr or ~/opt/openEMS etc.
+    % assume this file to be in  '<openEMS-path>/share/openEMS/matlab/private/'
+    % assume openEMS binary to be in '<openEMS-path>/bin'
+    openEMS_Path = [dir filesep '../../../../bin' filesep];
     openEMS_Path = [openEMS_Path 'openEMS.sh'];
 else
+    openEMS_Path = [dir filesep '../..' filesep];
     openEMS_Path = [openEMS_Path 'openEMS'];
 end