diff --git a/bin/crab.py b/bin/crab.py
index fafdfc97..ea3fe309 100755
--- a/bin/crab.py
+++ b/bin/crab.py
@@ -7,6 +7,7 @@
   - exit with the proper exit codes
 """
 from __future__ import print_function
+from __future__ import division
 import sys
 if sys.version_info < (2, 6):
     print('\nError: using a version of python < 2.6. Exiting...\n')
diff --git a/src/python/CRABClient/CredentialInteractions.py b/src/python/CRABClient/CredentialInteractions.py
index 79a2ad9e..0e3306ba 100644
--- a/src/python/CRABClient/CredentialInteractions.py
+++ b/src/python/CRABClient/CredentialInteractions.py
@@ -87,6 +87,8 @@ def createNewVomsProxy(self, timeLeftThreshold=0, proxyCreatedByCRAB=False, prox
             proxyTimeLeft = 0
         else:
             self.logger.debug("Found proxy file %s" % (proxyFileName))
+            self.logger.debug("Making sure it has proper VOMS extension")
+            proxy.validateVO()
             self.logger.debug("Getting proxy life time left")
             proxyTimeLeft = proxy.getTimeLeft()
             hours, minutes, seconds = int(proxyTimeLeft/3600), int((proxyTimeLeft%3600)/60), int((proxyTimeLeft%3600)%60)
diff --git a/src/python/CRABClient/ProxyInteractions.py b/src/python/CRABClient/ProxyInteractions.py
index 9c49238d..627a3686 100644
--- a/src/python/CRABClient/ProxyInteractions.py
+++ b/src/python/CRABClient/ProxyInteractions.py
@@ -58,6 +58,19 @@ def setVOGroupVORole(self, group, role):
     def getFilename(self):
         return self.proxyFile
 
+    def validateVO(self):
+        # make sure that proxy has a VOMS extension for CMS VirtualOrganization
+        cmd = 'voms-proxy-info --vo --file %s' % self.proxyFile
+        stdout, stderr, rc = execute_command(cmd, logger=self.logger)
+        if rc != 0 or 'cms' not in stdout:
+            msg = "\n".join(['Error executing %s:' % cmd, stdout, stderr])
+            self.logger.error(msg)
+            msg = 'proxy %s is not a valid proxy file or has no valid VOMS extension.\n' % self.proxyFile
+            stdout, stderr, rc = execute_command('voms-proxy-info -all', logger=self.logger)
+            msg += 'output of voms-proxy-info -all is\n%s' % (stdout+'\n'+stderr)
+            msg += '\n**** Make sure you do voms-proxy-init -voms cms ****\n'
+            raise ProxyCreationException(msg)
+
     def getTimeLeft(self):
         cmd = 'voms-proxy-info --actimeleft --timeleft --file %s' % self.proxyFile
         stdout, stderr, rc = execute_command(cmd, logger=self.logger)
diff --git a/src/python/CRABClient/WMCoreConfigWrapper.py b/src/python/CRABClient/WMCoreConfigWrapper.py
index 3a05bc13..dcce1130 100644
--- a/src/python/CRABClient/WMCoreConfigWrapper.py
+++ b/src/python/CRABClient/WMCoreConfigWrapper.py
@@ -17,6 +17,7 @@
 dependencies which are not available in CMSSW_8 or earlier, e.g. "future"
 """
 
+from __future__ import division
 from CRABClient.Configuration import Configuration as Config
 from CRABClient.ClientUtilities import colors
 
diff --git a/src/python/CRABClient/WMCoreConfiguration.py b/src/python/CRABClient/WMCoreConfiguration.py
index 70930328..5fdde5a5 100644
--- a/src/python/CRABClient/WMCoreConfiguration.py
+++ b/src/python/CRABClient/WMCoreConfiguration.py
@@ -11,6 +11,7 @@
 Module dealing with Configuration file in python format
 """
 
+from __future__ import division
 import imp
 import os
 import sys