diff --git a/src/modules/netinstall/NetInstallPage.cpp b/src/modules/netinstall/NetInstallPage.cpp
index 030537732..13c0da336 100644
--- a/src/modules/netinstall/NetInstallPage.cpp
+++ b/src/modules/netinstall/NetInstallPage.cpp
@@ -57,14 +57,6 @@ NetInstallPage::NetInstallPage( QWidget* parent )
     ui->setupUi( this );
 }
 
-bool
-NetInstallPage::isReady()
-{
-    // nothing to wait for, the data are immediately ready
-    // if the user does not select any group nothing is installed
-    return true;
-}
-
 bool
 NetInstallPage::readGroups( const QByteArray& yamlData )
 {
@@ -92,10 +84,13 @@ NetInstallPage::readGroups( const QByteArray& yamlData )
 void
 NetInstallPage::dataIsHere( QNetworkReply* reply )
 {
+    // If m_required is *false* then we still say we're ready
+    // even if the reply is corrupt or missing.
     if ( reply->error() != QNetworkReply::NoError )
     {
         cDebug() << reply->errorString();
         ui->netinst_status->setText( tr( "Network Installation. (Disabled: Unable to fetch package lists, check your network connection)" ) );
+        emit checkReady( !m_required );
         return;
     }
 
@@ -104,6 +99,7 @@ NetInstallPage::dataIsHere( QNetworkReply* reply )
         cDebug() << "Netinstall groups data was received, but invalid.";
         ui->netinst_status->setText( tr( "Network Installation. (Disabled: Unable to fetch package lists, check your network connection)" ) );
         reply->deleteLater();
+        emit checkReady( !m_required );
         return;
     }
 
@@ -112,7 +108,7 @@ NetInstallPage::dataIsHere( QNetworkReply* reply )
     ui->groupswidget->header()->setSectionResizeMode( 1, QHeaderView::Stretch );
 
     reply->deleteLater();
-    emit checkReady( isReady() );
+    emit checkReady( true );
 }
 
 QList<PackageTreeItem::ItemData> NetInstallPage::selectedPackages() const
@@ -139,6 +135,12 @@ void NetInstallPage::loadGroupList()
     m_networkManager.get( request );
 }
 
+void NetInstallPage::setRequired(bool b)
+{
+    m_required = b;
+}
+
+
 void NetInstallPage::onActivate()
 {
     ui->groupswidget->setFocus();
diff --git a/src/modules/netinstall/NetInstallPage.h b/src/modules/netinstall/NetInstallPage.h
index 423c16b8e..f6939cea6 100644
--- a/src/modules/netinstall/NetInstallPage.h
+++ b/src/modules/netinstall/NetInstallPage.h
@@ -46,13 +46,17 @@ public:
 
     void onActivate();
 
-    bool isReady();
-
     // Retrieves the groups, with name, description and packages, from
     // the remote URL configured in the settings. Assumes the URL is already
     // in the global storage. This should be called before displaying the page.
     void loadGroupList();
 
+    // Sets the "required" state of netinstall data. Influences whether
+    // corrupt or unavailable data causes checkReady() to be emitted
+    // true (not-required) or false.
+    void setRequired( bool );
+    bool getRequired() const { return m_required; }
+
     // Returns the list of packages belonging to groups that are
     // selected in the view in this given moment. No data is cached here, so
     // this function does not have constant time.
@@ -76,6 +80,7 @@ private:
     QNetworkAccessManager m_networkManager;
 
     PackageModel* m_groups;
+    bool m_required;
 };
 
 #endif // NETINSTALLPAGE_H
diff --git a/src/modules/netinstall/NetInstallViewStep.cpp b/src/modules/netinstall/NetInstallViewStep.cpp
index 347b2bf27..20505cc34 100644
--- a/src/modules/netinstall/NetInstallViewStep.cpp
+++ b/src/modules/netinstall/NetInstallViewStep.cpp
@@ -2,6 +2,7 @@
  *   Copyright 2016, Luca Giambonini <almack@chakraos.org>
  *   Copyright 2016, Lisa Vitolo <shainer@chakraos.org>
  *   Copyright 2017, Kyle Robbertze  <krobbertze@gmail.com>
+ *   Copyright 2017, Adriaan de Groot <groot@kde.org>
  *
  *   Calamares is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -30,11 +31,11 @@ CALAMARES_PLUGIN_FACTORY_DEFINITION( NetInstallViewStepFactory, registerPlugin<N
 NetInstallViewStep::NetInstallViewStep( QObject* parent )
     : Calamares::ViewStep( parent )
     , m_widget( new NetInstallPage() )
-    , m_nextEnabled( true )
+    , m_nextEnabled( false )
 {
     emit nextStatusChanged( true );
     connect( m_widget, &NetInstallPage::checkReady,
-             this, &NetInstallViewStep::nextStatusChanged );
+             this, &NetInstallViewStep::nextIsReady );
 }
 
 
@@ -178,6 +179,11 @@ NetInstallViewStep::onLeave()
 void
 NetInstallViewStep::setConfigurationMap( const QVariantMap& configurationMap )
 {
+    m_widget->setRequired(
+        configurationMap.contains( "required" ) &&
+        configurationMap.value( "required" ).type() == QVariant::Bool &&
+        configurationMap.value( "required" ).toBool() );
+
     if ( configurationMap.contains( "groupsUrl" ) &&
             configurationMap.value( "groupsUrl" ).type() == QVariant::String )
     {
@@ -186,3 +192,10 @@ NetInstallViewStep::setConfigurationMap( const QVariantMap& configurationMap )
         m_widget->loadGroupList();
     }
 }
+
+void
+NetInstallViewStep::nextIsReady( bool b )
+{
+    m_nextEnabled = b;
+    emit nextStatusChanged( b );
+}
diff --git a/src/modules/netinstall/NetInstallViewStep.h b/src/modules/netinstall/NetInstallViewStep.h
index d9853f26f..ee53f61ce 100644
--- a/src/modules/netinstall/NetInstallViewStep.h
+++ b/src/modules/netinstall/NetInstallViewStep.h
@@ -60,6 +60,9 @@ public:
 
     void setConfigurationMap( const QVariantMap& configurationMap ) override;
 
+public slots:
+    void nextIsReady( bool );
+
 private:
     NetInstallPage* m_widget;
     bool m_nextEnabled;
diff --git a/src/modules/netinstall/netinstall.conf b/src/modules/netinstall/netinstall.conf
index b87aef43e..f5977a267 100644
--- a/src/modules/netinstall/netinstall.conf
+++ b/src/modules/netinstall/netinstall.conf
@@ -1,2 +1,13 @@
 ---
+# This is the URL that is retrieved to get the netinstall groups-and-packages
+# data (which should be in the format described in netinstall.yaml).
 groupsUrl: http://chakraos.org/netinstall.php
+
+# If the installation can proceed without netinstall (e.g. the Live CD
+# can create a working installed system, but netinstall is preferred
+# to bring it up-to-date or extend functionality) leave this set to
+# false (the default). If set to true, the netinstall data is required.
+#
+# This only has an effect if the netinstall data cannot be retrieved,
+# or is corrupt: having "required" set, means the install cannot proceed.
+required: false