diff --git a/setup/management.sh b/setup/management.sh
index 14a51371..2dd1e957 100755
--- a/setup/management.sh
+++ b/setup/management.sh
@@ -7,7 +7,7 @@ echo "Installing Mail-in-a-Box system management daemon..."
 # build-essential libssl-dev libffi-dev python3-dev: Required to pip install cryptography.
 apt_install python3-flask links duplicity libyaml-dev python3-dnspython python3-dateutil \
 	build-essential libssl-dev libffi-dev python3-dev python-pip
-hide_output pip3 install --upgrade rtyaml email_validator idna cryptography boto
+hide_output pip3 install --upgrade rtyaml email_validator==1.0.0 idna>=2.0.0 cryptography==1.0 boto
 
 # duplicity uses python 2 so we need to use the python 2 package of boto
 hide_output pip install --upgrade boto
diff --git a/setup/questions.sh b/setup/questions.sh
index 9c267616..bfc751b3 100644
--- a/setup/questions.sh
+++ b/setup/questions.sh
@@ -13,7 +13,7 @@ if [ -z "$NONINTERACTIVE" ]; then
 	fi
 
 	# email_validator is repeated in setup/management.sh
-	hide_output pip3 install email_validator || exit 1
+	hide_output pip3 install email_validator==1.0.0 || exit 1
 
 	message_box "Mail-in-a-Box Installation" \
 		"Hello and thanks for deploying a Mail-in-a-Box!