diff --git a/README.rst b/README.rst
index b8b68848d..fae94aa7a 100644
--- a/README.rst
+++ b/README.rst
@@ -86,14 +86,14 @@ portable version you should observe the following install steps.*
    and Setuptools on your system.
 
    a. Download and run the `Python 32-bit MSI installer
-      <http://www.python.org/ftp/python/2.7.6/python-2.7.6.msi>`_. Note
+      <http://www.python.org/ftp/python/2.7.9/python-2.7.9.msi>`_. Note
       that the 32-bit MSI installer is required even on a 64-bit Windows
       system. If you use the 64-bit MSI installer, step 3 of this
       instruction will fail unless you installed the package reportlab
       manually.
 
    b. Add python directories to PATH (via Control Panel > System >
-      Advanced): ``";C:\\Python27;C:\\Python27\\Scripts"``. Note that the path
+      Advanced): ``";C:\Python27;C:\Python27\Scripts"``. Note that the path
       can differ if you customized the install of Python in the first step.
 
    c. Download and run (via double click) the last `install script
@@ -110,7 +110,7 @@ portable version you should observe the following install steps.*
    To install Virtual Python Environment builder, open command line (cmd)
    and run::
 
-       > easy_install https://pypi.python.org/packages/source/v/virtualenv/virtualenv-1.11.6.tar.gz
+       > easy_install https://pypi.python.org/packages/source/v/virtualenv/virtualenv-12.0.5.tar.gz
 
    Create your OpenSlides directory, change to it, setup and activate the
    virtual environment::
diff --git a/extras/win32-portable/create_portable.txt b/extras/win32-portable/create_portable.txt
index a6d2edbfd..a7138c19b 100644
--- a/extras/win32-portable/create_portable.txt
+++ b/extras/win32-portable/create_portable.txt
@@ -5,34 +5,21 @@ How to create a new portable Windows distribution of OpenSlides:
    Follow the instructions in the README, section III (Windows installation), step 1.
 
 
-2. Install all required python packages (see requirements_production.txt):
+2. Install all required python packages from requirements_production.txt:
+   (Note: You have to use 'easy_install -Z $PACKAGENAME')
 
-       easy_install -Z "django<1.7" ^
-            backports.ssl_match_hostname ^
-            "beautifulsoup4<4.4" ^
-            "bleach<1.5" ^
-            "django-ckeditor-updated<4.3" ^
-            "django-haystack<2.2" ^
-            "django-mptt<0.7" ^
-            "jsonfield<0.10" ^
-            "natsort<3.3" ^
-            "reportlab<2.8" ^
-            "roman<2.1" ^
-            "sockjs_tornado<1.1" ^
-            "tornado<3.3" ^
-            "whoosh<2.6" ^
-            "setuptools<3.7"
+       python install-requirements.py
 
 
 3. Install pywin32 from binary installer:
-   http://sourceforge.net/projects/pywin32/files/pywin32/Build%20218/pywin32-218.win32-py2.7.exe/download
+   http://sourceforge.net/projects/pywin32/files/pywin32/Build%20219/pywin32-219.win32-py2.7.exe/download
 
    Pywin32 is used to update the version resource of the prebuild openslides.exe.
    It is not strictly required but at least for published releases it is highly advisable.
 
 
 4. Install wxPython from binary installer:
-   http://downloads.sourceforge.net/wxpython/wxPython2.8-win32-unicode-2.8.12.1-py27.exe
+   http://sourceforge.net/projects/wxpython/files/wxPython/2.8.12.1/wxPython2.8-win32-unicode-2.8.12.1-py27.exe/download
 
    WxPython is required to build the OpenSlides GUI frontend.
 
diff --git a/extras/win32-portable/install-requirements.py b/extras/win32-portable/install-requirements.py
new file mode 100644
index 000000000..c2dfaa3c2
--- /dev/null
+++ b/extras/win32-portable/install-requirements.py
@@ -0,0 +1,12 @@
+import os
+
+f = open("../../requirements_production.txt")
+reqs = f.read().split("\n")
+
+for req in reqs:
+    # ignore comments or pip options
+    if req.startswith('--') or req.startswith('#'):
+        continue
+    # ignore blank lines
+    if len(req) > 0:
+        os.system('easy_install -Z -U "%s"' % req)
diff --git a/openslides/core/chatbox.py b/openslides/core/chatbox.py
index be5d0b728..614380465 100644
--- a/openslides/core/chatbox.py
+++ b/openslides/core/chatbox.py
@@ -3,8 +3,9 @@
 from datetime import datetime
 
 from django.conf import settings
-from django.contrib.sessions.models import Session
 from django.utils.html import urlize
+from django.utils.importlib import import_module
+
 from sockjs.tornado import SockJSConnection
 
 
@@ -20,22 +21,25 @@ class ChatboxSocketHandler(SockJSConnection):
         """
         from openslides.participant.models import User
 
-        # TODO: Use the django way to get the session to be compatible with
-        # other auth-backends; see comment in pull request #1220:
-        # https://github.com/OpenSlides/OpenSlides/pull/1220#discussion_r11565705
-        session_key = info.get_cookie(settings.SESSION_COOKIE_NAME).value
-        session = Session.objects.get(session_key=session_key)
+        # get the session (compatible with other auth-backends)
+        engine = import_module(settings.SESSION_ENGINE)
         try:
-            self.user = User.objects.get(pk=session.get_decoded().get('_auth_user_id'))
+            session_key = info.get_cookie(settings.SESSION_COOKIE_NAME).value
+            session = engine.SessionStore(session_key)
+            pk = session.get_decoded().get('_auth_user_id')
+        except AttributeError:
+            return False
+
+        try:
+            self.user = User.objects.get(pk)
         except User.DoesNotExist:
-            return_value = False
+            return False
+
+        if self.user.has_perm('core.can_use_chat'):
+            self.clients.add(self)
+            return True
         else:
-            if self.user.has_perm('core.can_use_chat'):
-                self.clients.add(self)
-                return_value = True
-            else:
-                return_value = False
-        return return_value
+            return False
 
     def on_message(self, message):
         """