diff --git a/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.inx b/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.inx
index 4c2d9ce..c9b5642 100644
--- a/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.inx
+++ b/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.inx
@@ -6,7 +6,7 @@
         <param name="tab" type="notebook">
             <page name="tab_settings" gui-text="Upgrade Options">
                 <label appearance="header">Install Updates / Options</label>
-                <param name="install_requirements" type="bool" gui-text="Install python requirements" gui-description="Installs all python requirements from requirements.txt. This may take up to 10 minutes or may. There will be no visible console output until finished. Please wait until completed.">false</param>
+                <param name="install_requirements" type="bool" gui-text="Install/upgrade python requirements" gui-description="Installs/upgrades all python requirements from requirements.txt. This may take up to 10 minutes or may. There will be no visible console output until finished. Please wait until completed.">false</param>
 
                 <param name="convert_to_git" type="bool" gui-text="Convert to .git" gui-description="If you downloaded MightyScape as .zip or .tar.gz you cannot upgrade using this extension. But you can convert your downloaded directory to a .git one by enabling this option">false</param>
                 <param name="recreate_remotes" type="bool" gui-text="Recreate remotes" gui-description="Update remotes in git config file (useful if you have an older version of MightyScape or if something changes). Warning: might drop passwords/auth tokens!">false</param>
diff --git a/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.py b/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.py
index 40ea78b..16d1c1a 100644
--- a/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.py
+++ b/extensions/fablabchemnitz/about_upgrade_mightyscape/about_upgrade_mightyscape.py
@@ -36,8 +36,15 @@ class AboutUpgradeMightyScape(inkex.EffectExtension):
         if not os.path.exists(requirements):
             inkex.utils.debug("requirements.txt could not be found.")
             exit(1)
-        command = ["python3 -m pip install --upgrade --quiet --no-cache-dir -r " + requirements]
-        inkex.utils.debug("Executing: {}".format(command))
+
+        if os.name=="nt":
+            PYTHONBIN = "pythonw.exe"
+        else: #Linux/MacOS
+            PYTHONBIN = "python"
+
+        python_venv = os.path.abspath(os.path.join(os.path.dirname(git.__file__), '../', '../', '../', '../', 'bin', PYTHONBIN))
+        command = ["{} -m pip install --upgrade --quiet --no-cache-dir -r ".format(python_venv) + requirements]
+        inkex.utils.debug("Executing: {}".format(command[0]))
         proc = subprocess.Popen(command, shell=True, stdout=PIPE, stderr=PIPE)
         stdout, stderr = proc.communicate()
         inkex.utils.debug(stdout.decode('UTF-8'))