diff --git a/phpBB/adm/style/acp_ext_enable.html b/phpBB/adm/style/acp_ext_enable.html
index 2a8c638b1d..670904a2ce 100644
--- a/phpBB/adm/style/acp_ext_enable.html
+++ b/phpBB/adm/style/acp_ext_enable.html
@@ -5,7 +5,7 @@
 	<h1>{L_EXTENSIONS_ADMIN}</h1>
 
 	<p>{L_EXTENSIONS_EXPLAIN}</p>
-	<p><!-- IF IS_ENABLING -->{L_EXTENSION_ENABLE_EXPLAIN}<!-- ELSE -->{L_EXTENSION_INSTALL_EXPLAIN}<!-- ENDIF --></p>
+	<p>{L_EXTENSION_ENABLE_EXPLAIN}</p>
 
 	<!-- IF MIGRATOR_ERROR -->
 	<div class="errorbox">
@@ -20,18 +20,18 @@
 
 	<form id="acp_extensions" method="post" action="{U_ENABLE}">
 	<fieldset class="submit-buttons">
-		<legend><!-- IF IS_ENABLING -->{L_EXTENSION_ENABLE}<!-- ELSE -->{L_EXTENSION_INSTALL}<!-- ENDIF --></legend>
-		<input class="button1" type="submit" name="enable" value="<!-- IF IS_ENABLING -->{L_EXTENSION_ENABLE}<!-- ELSE -->{L_EXTENSION_INSTALL}<!-- ENDIF -->" />
+		<legend>{L_EXTENSION_ENABLE}</legend>
+		<input class="button1" type="submit" name="enable" value="{L_EXTENSION_ENABLE}" />
 		<input class="button2" type="submit" name="cancel" value="{L_CANCEL}" />
 	</fieldset>
 	</form>
 	<!-- ELSEIF S_NEXT_STEP -->
 		<div class="errorbox">
-			<p><!-- IF IS_ENABLING -->{L_EXTENSION_ENABLE_IN_PROGRESS}<!-- ELSE -->{L_EXTENSION_INSTALL_IN_PROGRESS}<!-- ENDIF --></p>
+			<p>{L_EXTENSION_ENABLE_IN_PROGRESS}</p>
 		</div>
 	<!-- ELSE -->
 		<div class="successbox">
-			<p><!-- IF IS_ENABLING -->{L_EXTENSION_ENABLE_SUCCESS}<!-- ELSE -->{L_EXTENSION_INSTALL_SUCCESS}<!-- ENDIF --></p>
+			<p>{L_EXTENSION_ENABLE_SUCCESS}</p>
 			<br />
 			<p><a href="{U_RETURN}">{L_RETURN_TO_EXTENSION_LIST}</a></p>
 		</div>
diff --git a/phpBB/includes/acp/acp_extensions.php b/phpBB/includes/acp/acp_extensions.php
index da5a58c7d6..7ca98221c0 100644
--- a/phpBB/includes/acp/acp_extensions.php
+++ b/phpBB/includes/acp/acp_extensions.php
@@ -83,7 +83,6 @@ class acp_extensions
 			break;
 
 			case 'enable_pre':
-			case 'install_pre':
 				if (!$md_manager->validate_enable())
 				{
 					trigger_error($user->lang['EXTENSION_NOT_AVAILABLE'] . adm_back_link($this->u_action), E_USER_WARNING);
@@ -98,14 +97,12 @@ class acp_extensions
 
 				$template->assign_vars(array(
 					'PRE'				=> true,
-					'IS_ENABLING'		=> $action == 'enable_pre',
-					'L_CONFIRM_MESSAGE'	=> $this->user->lang('EXTENSION_' . (($action == 'enable_pre') ? 'ENABLE' : 'INSTALL') . '_CONFIRM', $md_manager->get_metadata('display-name')),
-					'U_ENABLE'			=> $this->u_action . '&amp;action=' . (($action == 'enable_pre') ? 'enable' : 'install') . '&amp;ext_name=' . urlencode($ext_name),
+					'L_CONFIRM_MESSAGE'	=> $this->user->lang('EXTENSION_ENABLE_CONFIRM', $md_manager->get_metadata('display-name')),
+					'U_ENABLE'			=> $this->u_action . '&amp;action=enable&amp;ext_name=' . urlencode($ext_name),
 				));
 			break;
 
 			case 'enable':
-			case 'install':
 				if (!$md_manager->validate_enable())
 				{
 					trigger_error($user->lang['EXTENSION_NOT_AVAILABLE'] . adm_back_link($this->u_action), E_USER_WARNING);
@@ -120,7 +117,7 @@ class acp_extensions
 						{
 							$template->assign_var('S_NEXT_STEP', true);
 
-							meta_refresh(0, $this->u_action . '&amp;action=' . $action . '&amp;ext_name=' . urlencode($ext_name));
+							meta_refresh(0, $this->u_action . '&amp;action=enable&amp;ext_name=' . urlencode($ext_name));
 						}
 					}
 				}
@@ -132,7 +129,6 @@ class acp_extensions
 				$this->tpl_name = 'acp_ext_enable';
 
 				$template->assign_vars(array(
-					'IS_ENABLING'	=> $action == 'enable',
 					'U_RETURN'		=> $this->u_action . '&amp;action=list',
 				));
 			break;
@@ -309,7 +305,7 @@ class acp_extensions
 				));
 
 				$this->output_actions('disabled', array(
-					'INSTALL'		=> $this->u_action . '&amp;action=install_pre&amp;ext_name=' . urlencode($name),
+					'ENABLE'		=> $this->u_action . '&amp;action=enable_pre&amp;ext_name=' . urlencode($name),
 				));
 			}
 			catch(\phpbb\extension\exception $e)
diff --git a/phpBB/language/en/acp/extensions.php b/phpBB/language/en/acp/extensions.php
index 96eed14c0e..5421789e68 100644
--- a/phpBB/language/en/acp/extensions.php
+++ b/phpBB/language/en/acp/extensions.php
@@ -49,22 +49,18 @@ $lang = array_merge($lang, array(
 
 	'EXTENSION_DISABLE'		=> 'Disable',
 	'EXTENSION_ENABLE'		=> 'Enable',
-	'EXTENSION_INSTALL'		=> 'Install',
 	'EXTENSION_UNINSTALL'	=> 'Uninstall',
 
 	'EXTENSION_DISABLE_EXPLAIN'		=> 'Disabling an extension retains its files, data and settings but removes any functionality added by the extension.',
 	'EXTENSION_ENABLE_EXPLAIN'		=> 'Enabling an extension allows you to use it on your board.',
-	'EXTENSION_INSTALL_EXPLAIN'		=> 'Installing an extension will perform database changes that are required to use the extension on your board.',
 	'EXTENSION_UNINSTALL_EXPLAIN'	=> 'Uninstalling an extension removes all of its data and settings. The extension files are retained so it can be installed again.',
 
 	'EXTENSION_DISABLE_IN_PROGRESS'	=> 'The extension is currently being disabled, please do not leave or refresh this page until it is completed.',
 	'EXTENSION_ENABLE_IN_PROGRESS'	=> 'The extension is currently being enabled, please do not leave or refresh this page until it is completed.',
-	'EXTENSION_INSTALL_IN_PROGRESS'	=> 'The extension is currently being installed, please do not leave or refresh this page until it is completed.',
 	'EXTENSION_UNINSTALL_IN_PROGRESS'	=> 'The extension is currently being uninstalled, please do not leave or refresh this page until it is completed.',
 
 	'EXTENSION_DISABLE_SUCCESS'		=> 'The extension was disabled successfully',
 	'EXTENSION_ENABLE_SUCCESS'		=> 'The extension was enabled successfully',
-	'EXTENSION_INSTALL_SUCCESS'		=> 'The extension was installed successfully',
 	'EXTENSION_UNINSTALL_SUCCESS'	=> 'The extension was uninstalled successfully',
 
 	'EXTENSION_NAME'		=> 'Extension Name',
@@ -73,7 +69,6 @@ $lang = array_merge($lang, array(
 
 	'EXTENSION_DISABLE_CONFIRM'		=> 'Are you sure that you wish to disable the “%s” extension?',
 	'EXTENSION_ENABLE_CONFIRM'		=> 'Are you sure that you wish to enable the “%s” extension?',
-	'EXTENSION_INSTALL_CONFIRM'		=> 'Are you sure that you wish to install the “%s” extension?',
 	'EXTENSION_UNINSTALL_CONFIRM'	=> 'Are you sure that you wish to uninstall the “%s” extension? This will remove all data and settings stored for this extension and cannot be undone!',
 
 	'RETURN_TO_EXTENSION_LIST'	=> 'Return to the extension list',