diff --git a/doc/user_download_and_install_linux.rst b/doc/user_download_and_install_linux.rst
index 91f546bf..8da2dd4f 100644
--- a/doc/user_download_and_install_linux.rst
+++ b/doc/user_download_and_install_linux.rst
@@ -43,7 +43,7 @@ Choose a suitable directory, e.g. ``~/build``, download and unpack the archive
 
     mkdir -p ~/build
     cd ~/build
-    curl -O https://github.com/theochem/horton/releases/download/2.0.0/horton-2.0.0.tar.gz
+    curl -kLO https://github.com/theochem/horton/releases/download/2.0.0/horton-2.0.0.tar.gz
     tar -xvzf horton-2.0.0.tar.gz
     cd horton-2.0.0
 
diff --git a/doc/user_download_and_install_mac.rst b/doc/user_download_and_install_mac.rst
index 6bbb723b..d26d4da9 100644
--- a/doc/user_download_and_install_mac.rst
+++ b/doc/user_download_and_install_mac.rst
@@ -101,7 +101,7 @@ Choose a suitable directory, e.g. ``~/build``, download and unpack the archive:
 
     mkdir -p ~/build
     cd ~/build
-    curl -O https://github.com/theochem/horton/releases/download/2.0.0/horton-2.0.0.tar.gz
+    curl -kLO https://github.com/theochem/horton/releases/download/2.0.0/horton-2.0.0.tar.gz
     tar -xvzf horton-2.0.0.tar.gz
     cd horton-2.0.0
 
diff --git a/updateversion.py b/updateversion.py
index e5014e63..de06c34c 100755
--- a/updateversion.py
+++ b/updateversion.py
@@ -30,11 +30,11 @@
     ('horton/__init__.py', '^__version__ = \'(...+)\'$'),
     ('doc/conf.py', '        release = \'(...+)-nogit\'$'),
     ('doc/user_download_and_install_linux.rst', '^    https://github.com/theochem/horton/releases/download/(...+)/horton-(...+).tar.gz$'),
-    ('doc/user_download_and_install_linux.rst', '^    curl -O https://github.com/theochem/horton/releases/download/(...+)/horton-(...+).tar.gz$'),
+    ('doc/user_download_and_install_linux.rst', '^    curl -kLO https://github.com/theochem/horton/releases/download/(...+)/horton-(...+).tar.gz$'),
     ('doc/user_download_and_install_linux.rst', '^    tar -xvzf horton-(...+).tar.gz$'),
     ('doc/user_download_and_install_linux.rst', '^    cd horton-(...+)$'),
     ('doc/user_download_and_install_mac.rst', '^    https://github.com/theochem/horton/releases/download/(...+)/horton-(...+).tar.gz$'),
-    ('doc/user_download_and_install_mac.rst', '^    curl -O https://github.com/theochem/horton/releases/download/(...+)/horton-(...+).tar.gz$'),
+    ('doc/user_download_and_install_mac.rst', '^    curl -kLO https://github.com/theochem/horton/releases/download/(...+)/horton-(...+).tar.gz$'),
     ('doc/user_download_and_install_mac.rst', '^    tar -xvzf horton-(...+).tar.gz$'),
     ('doc/user_download_and_install_mac.rst', '^    cd horton-(...+)$'),
 ]