diff --git a/controller/main.php b/controller/main.php
index 2d61fba6..ea3d9c30 100644
--- a/controller/main.php
+++ b/controller/main.php
@@ -83,6 +83,9 @@ class main
 	/** @var int Allowed columns */
 	protected $allowed_columns;
 
+	/** @var bool Portal active flag */
+	protected $portal_active = false;
+
 	/**
 	* Constructor
 	* NOTE: The parameters of this method must match in order and type with
@@ -133,8 +136,17 @@ class main
 	*/
 	public function handle($columns = array())
 	{
+		// Do not run portal if it's already active
+		if ($this->portal_active)
+		{
+			return;
+		}
+
 		$this->controller_helper->run_initial_tasks();
 
+		// Set portal active
+		$this->portal_active = true;
+
 		// Check if we should limit the columns to display
 		$this->set_allowed_columns($columns);
 
diff --git a/tests/mock/template.php b/tests/mock/template.php
index 8806962f..36fc4caa 100644
--- a/tests/mock/template.php
+++ b/tests/mock/template.php
@@ -58,4 +58,9 @@ class template
 	{
 		$this->test_case->assertSame($expected, $this->data[$row]);
 	}
+
+	public function delete_var($key)
+	{
+		unset($this->data[$key]);
+	}
 }
diff --git a/tests/unit/controller/main_test.php b/tests/unit/controller/main_test.php
index 6eb1109f..69973fd0 100644
--- a/tests/unit/controller/main_test.php
+++ b/tests/unit/controller/main_test.php
@@ -91,4 +91,13 @@ class main_test extends \board3\portal\tests\testframework\database_test_case
 		$this->assertNull($this->controller_main->handle(array('left' => 1)));
 		$this->template->assert_same(true, 'S_PORTAL_ALL');
 	}
+
+	public function test_display_all_pages_twice()
+	{
+		$this->assertNull($this->controller_main->handle(array('left' => 1)));
+		$this->template->assert_same(true, 'S_PORTAL_ALL');
+		$this->template->delete_var('S_PORTAL_ALL');
+		$this->assertNull($this->controller_main->handle(array('left' => 1)));
+		$this->template->assert_same(null, 'S_PORTAL_ALL');
+	}
 }