diff --git a/DDCore/python/dd4hepFactories.py b/DDCore/python/dd4hepFactories.py
index ce72655990dd52d2eeb9a9e7bb908eb29c58ed57..71eba0ba1d97cb3610b0b34f05d5a96fbeffee79 100755
--- a/DDCore/python/dd4hepFactories.py
+++ b/DDCore/python/dd4hepFactories.py
@@ -104,7 +104,7 @@ class ComponentDumper:
                                             "<D>  to DUMP the list of components \n"+
                                             "<S>  to SKIP this particular library\n"+
                                             "<L>  to no longer LOAD libraries    \n")
-                        except Exception,X:
+                        except Exception as X:
                             ret = 'D'
                     if not len(ret):
                        ret = 'D'
@@ -156,13 +156,13 @@ try:
   from ROOT import gROOT
   from ROOT import gSystem
   gROOT.SetBatch(1)
-except ImportError,X:
+except ImportError as X:
   logger.error('PyROOT interface not accessible: %s',str(X))
   sys.exit(errno.ENOENT)
 
 try:
   import dd4hep
-except ImportError,X:
+except ImportError as X:
   logger.error('dd4hep python interface not accessible: %s',str(X))
   sys.exit(errno.ENOENT)
 
diff --git a/DDG4/examples/readHEPMC.py b/DDG4/examples/readHEPMC.py
index 43cbf49da9a852dcb6bb5b4a52724c277c1a7841..4e70ce2404dc776e3ff937319bbaef4177ffcd30 100644
--- a/DDG4/examples/readHEPMC.py
+++ b/DDG4/examples/readHEPMC.py
@@ -31,7 +31,7 @@ def run(input_file):
     try:
       ret = gen.readParticles(evtid,prim_vtx,parts)
       evtid = evtid + 1
-    except Exception,X:
+    except Exception as X:
       logger.error( '\nException: readParticles: %s',str(X))
       ret = None
     if ret:
diff --git a/DDG4/python/checkGeometry.py b/DDG4/python/checkGeometry.py
index 813ce657aadc1908901c0d7ad47d67d3db84b1a9..b5e6dcec122847b414991431cc7495ec0098c62d 100755
--- a/DDG4/python/checkGeometry.py
+++ b/DDG4/python/checkGeometry.py
@@ -63,13 +63,13 @@ try:
   import ROOT
   from ROOT import gROOT
   gROOT.SetBatch(1)
-except ImportError,X:
+except ImportError as X:
   logger.error('PyROOT interface not accessible: %s',str(X))
   sys.exit(errno.ENOENT)
 
 try:
   import dd4hep
-except ImportError,X:
+except ImportError as X:
   logger.error('dd4hep python interface not accessible: %s',str(X))
   sys.exit(errno.ENOENT)
 
diff --git a/DDG4/python/checkOverlaps.py b/DDG4/python/checkOverlaps.py
index 2ea26a344c0fa3d2c4174bc1ed27b08334f3031c..b687439b898571d2dca0b9bf1099ec5725426e50 100755
--- a/DDG4/python/checkOverlaps.py
+++ b/DDG4/python/checkOverlaps.py
@@ -47,14 +47,14 @@ try:
   import ROOT
   from ROOT import gROOT
   gROOT.SetBatch(1)
-except ImportError,X:
+except ImportError as X:
   logger.error('PyROOT interface not accessible: %s',str(X))
   logger.error("%s",parser.format_help())
   sys.exit(errno.ENOENT)
 
 try:
   import dd4hep
-except ImportError,X:
+except ImportError as X:
   logger.error('dd4hep python interface not accessible: %s',str(X))
   logger.error("%s",parser.format_help())
   sys.exit(errno.ENOENT)
diff --git a/DDG4/python/g4MaterialScan.py b/DDG4/python/g4MaterialScan.py
index c5029e32004e5ae4dc072f810a16c2d52167701d..c5698a0d7b1b574a90be2335327c37a37c6843ec 100644
--- a/DDG4/python/g4MaterialScan.py
+++ b/DDG4/python/g4MaterialScan.py
@@ -107,14 +107,14 @@ try:
   import ROOT
   from ROOT import gROOT
   gROOT.SetBatch(1)
-except ImportError,X:
+except ImportError as X:
   logger.error('PyROOT interface not accessible: %s', X)
   logger.info(parser.format_help())
   sys.exit(errno.ENOENT)
 
 try:
   import DDG4, SystemOfUnits
-except ImportError,X:
+except ImportError as X:
   logger.error('DDG4 python interface not accessible: %s', X)
   logger.info(parser.format_help())
   sys.exit(errno.ENOENT)
diff --git a/DDRec/python/dumpDetectorData.py b/DDRec/python/dumpDetectorData.py
index f317a4f742007f2a097887d5e635953ecc7a6c74..e8af8ded259d819227e2c4bfcb43082ec506ff4f 100644
--- a/DDRec/python/dumpDetectorData.py
+++ b/DDRec/python/dumpDetectorData.py
@@ -67,21 +67,21 @@ try:
   import ROOT
   from ROOT import gROOT
   gROOT.SetBatch(1)
-except ImportError,X:
+except ImportError as X:
   logger.error('PyROOT interface not accessible: %s',str(X))
   logger.error("%s",parser.format_help())
   sys.exit(errno.ENOENT)
 
 try:
   import dd4hep
-except ImportError,X:
+except ImportError as X:
   logger.error('dd4hep python interface not accessible: %s',str(X))
   logger.error("%s",parser.format_help())
   sys.exit(errno.ENOENT)
 #
 try:
   import DDRec
-except ImportError,X:
+except ImportError as X:
   logger.error('ddrec python interface not accessible: %s',str(X))
   logger.error("%s",parser.format_help())
   sys.exit(errno.ENOENT)