diff --git a/DDCore/python/dd4hepFactories.py b/DDCore/python/dd4hepFactories.py
index 4a77012e9..6a43b20e3 100755
--- a/DDCore/python/dd4hepFactories.py
+++ b/DDCore/python/dd4hepFactories.py
@@ -27,7 +27,10 @@ def __init__(self):
     self.all_components = []
 
   def scanPath(self):
-    ldp = os.environ['LD_LIBRARY_PATH'].split(':')
+    if os.getenv("LD_LIBRARY_PATH") is not None:
+      ldp = os.environ['LD_LIBRARY_PATH'].split(':')
+    else:
+      ldp = [ '/usr/lib64', '/usr/lib/', '/usr/local/lib', '/usr/lib64/root', '/usr/lib/root', '/usr/local/lib/root' ]
     for p in ldp:
       if len(p):
         logger.info('+== Search component directory: ' + p)
diff --git a/DDCore/python/dd4hep_base.py b/DDCore/python/dd4hep_base.py
index 64328ef28..7bb6c4b5e 100644
--- a/DDCore/python/dd4hep_base.py
+++ b/DDCore/python/dd4hep_base.py
@@ -25,13 +25,24 @@ def compileAClick(dictionary, g4=True):
   """
   from ROOT import gInterpreter, gSystem
   import os.path
-  dd4hep = os.environ['DD4hepINSTALL']
-  inc = ' -I' + os.environ['ROOTSYS'] + '/include -I' + dd4hep + '/include '
-  lib = ' -L' + dd4hep + '/lib -lDDCore -lDDG4 -lDDSegmentation '
+  if os.getenv("DD4hepINSTALL") is not None:
+    dd4hep = os.environ['DD4hepINSTALL']
+  else:
+    dd4hep = "/usr"
+  if os.getenv("ROOTSYS") is not None:
+    rootsys = os.environ['ROOTSYS']
+  else:
+    rootsys = "/usr"
+
+  inc = ' -I' + rootsys + '/include -I' + dd4hep + '/include '
+  lib = ' -L' + dd4hep + '/lib64 '+ ' -L' + dd4hep + '/lib -lDDCore -lDDG4 -lDDSegmentation '
   if g4:
-    geant4 = os.environ['G4INSTALL']
+    if os.getenv("G4INSTALL") is not None:
+      geant4 = os.environ['G4INSTALL']
+    else:
+      geant4 = "/usr"
     inc = inc + ' -I' + geant4 + '/include/Geant4 -Wno-shadow -g -O0 '
-    lib = lib + ' -L' + geant4 + '/lib  -L' + geant4 + '/lib64 -lG4event -lG4tracking -lG4particles '
+    lib = lib + ' -L' + geant4 + '/lib64  -L' + geant4 + '/lib -lG4event -lG4tracking -lG4particles '
 
   gSystem.AddIncludePath(inc)
   gSystem.AddLinkedLibs(lib)
@@ -50,7 +61,14 @@ def loaddd4hep():
   import os
   import sys
   # Add ROOT to the python path in case it is not yet there....
-  sys.path.append(os.environ['ROOTSYS'] + os.sep + 'lib')
+  if os.getenv("ROOTSYS") is not None:
+    rootsys = os.environ['ROOTSYS']
+  else:
+    rootsys = "/usr"
+  sys.path.append(rootsys + os.sep + 'lib')
+  sys.path.append(rootsys + os.sep + 'lib64')
+  sys.path.append(rootsys + os.sep + 'lib' + os.sep +'root')
+  sys.path.append(rootsys + os.sep + 'lib64' + os.sep +'root')
   from ROOT import gSystem
 
   import platform
diff --git a/GaudiPluginService/src/PluginServiceV1.cpp b/GaudiPluginService/src/PluginServiceV1.cpp
index d0f741bb7..c814730d3 100644
--- a/GaudiPluginService/src/PluginServiceV1.cpp
+++ b/GaudiPluginService/src/PluginServiceV1.cpp
@@ -156,9 +156,10 @@ namespace Gaudi {
           const char  sep    = ':';
 #endif
           char* search_path = ::getenv( envVar );
-          if ( search_path ) {
+          if ( true ) {
             logger().debug( std::string( "searching factories in " ) + envVar );
-            std::string            path( search_path );
+            std::string            path;
+            if ( search_path ) path = std::string(search_path); else path="/usr/lib64:/usr/lib:/usr/local/lib";
             std::string::size_type pos    = 0;
             std::string::size_type newpos = 0;
             while ( pos != std::string::npos ) {
diff --git a/GaudiPluginService/src/PluginServiceV2.cpp b/GaudiPluginService/src/PluginServiceV2.cpp
index 7b520e75f..06da671ec 100644
--- a/GaudiPluginService/src/PluginServiceV2.cpp
+++ b/GaudiPluginService/src/PluginServiceV2.cpp
@@ -158,7 +158,7 @@ namespace Gaudi {
 
           std::string search_path;
           const char* envPtr = std::getenv( envVar.c_str() );
-          if ( envPtr ) search_path = envPtr;
+          if ( envPtr ) search_path = envPtr; else search_path="/usr/lib64:/usr/lib:/usr/local/lib";
           if ( search_path.empty() ) {
             return;
           }