diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/Cache.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/Cache.js
index eb071d9a8d22e7704adfcd8ebe612f47f45ede14..f2802740969c0bf548ecddade6a2073712c5beb5 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/Cache.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/Cache.js
@@ -49,6 +49,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 								$outputContainer.append(message);
 							}));
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ChangeInstallToolPassword.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ChangeInstallToolPassword.js
index 0f518e0deaa6f6f3b17de68d563410be339388a8..c8bb85a9b2000423d117f398c0ee0006ec7d8a46 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ChangeInstallToolPassword.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ChangeInstallToolPassword.js
@@ -55,6 +55,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.append(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTables.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTables.js
index 0f3a34efe81d35e1a8f83cf38349265e36817a54..8f8c6073b5942ad5b6a321afec4bb8ea95269006 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTables.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTables.js
@@ -89,7 +89,14 @@ define([
 							});
 							$statContainer.find(self.selectorStatLastRuler + ':last').remove();
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.append(message);
 					}
+				},
+				error: function () {
+					var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+					$outputContainer.append(message);
 				}
 			});
 		},
@@ -118,6 +125,9 @@ define([
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.append(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.append(message);
 					}
 				},
 				error: function () {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTypo3tempFiles.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTypo3tempFiles.js
index a6ee77878088259ec8a49458de2df389412b30a0..dcb06fae0a4ad66ca988fc883c8b7b7c547ac3b5 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTypo3tempFiles.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ClearTypo3tempFiles.js
@@ -56,6 +56,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.html(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function () {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/CreateAdmin.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/CreateAdmin.js
index 849c49fbdfbe40fd7710667eab5cba5c4a731b9f..230384b43fc04df24c11bcde2d5a491ceeeae2c7 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/CreateAdmin.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/CreateAdmin.js
@@ -57,6 +57,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.html(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function () {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/DatabaseAnalyzer.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/DatabaseAnalyzer.js
index 313c0e98426d60fc74c21660f66e315d00d8ed1d..cb7c26dd928bd7c206b09a0fb33a2827744ce5e5 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/DatabaseAnalyzer.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/DatabaseAnalyzer.js
@@ -112,6 +112,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 							$(self.selectorExecuteTrigger).prop('disabled', false);
 							$(self.selectorAnalyzeTrigger).prop('disabled', false);
 						}
+					} else {
+						var message = InfoBox.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/DumpAutoload.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/DumpAutoload.js
index e219c30eb9e16c15076e2856674bce9168e5043a..a042e9bf444d78f28f4c7284bb63ee0442a2da6a 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/DumpAutoload.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/DumpAutoload.js
@@ -49,6 +49,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 								$outputContainer.append(message);
 							}));
 						}
+					} else {
+						var message = InfoBox.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/EnvironmentCheck.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/EnvironmentCheck.js
index 4f0a8aeb83241caa37bda392070944fe5c20bdb8..55ca1b17e0d70dce59c993917011f973bd1f339a 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/EnvironmentCheck.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/EnvironmentCheck.js
@@ -79,6 +79,9 @@ define([
                         } else if (warningCount > 0) {
                             $errorBadge.removeClass('label-error').addClass('label-warning').text(warningCount).show();
                         }
+                    } else {
+                      var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+                      $outputContainer.empty().append(message);
                     }
                 },
                 error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ExtensionScanner.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ExtensionScanner.js
index 82335067aeff720da94d94733c47f3bebc6fb4ba..ad2707f3c533808a184191cff92e47ae56b484f8 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ExtensionScanner.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ExtensionScanner.js
@@ -25,7 +25,7 @@ define(['jquery', 'TYPO3/CMS/Backend/Notification'], function($, Notification) {
 
 		initialize: function() {
 			var self = this;
-			$(document).on('click', this.selectorScanSingleTrigger,  function(e) {
+			$(document).on('click', this.selectorScanSingleTrigger, function(e) {
 				// Scan a single extension
 				var extension = $(e.target).data('extension');
 				e.preventDefault();
@@ -293,6 +293,9 @@ define(['jquery', 'TYPO3/CMS/Backend/Notification'], function($, Notification) {
 						} else {
 							Notification.warning('No files found', 'The extension EXT:' + extension + ' contains no files we can scan');
 						}
+					} else {
+						Notification.error('Oops, an error occurred', 'Please look at the console output for details');
+						console.error(data);
 					}
 				},
 				error: function(data) {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/FolderStructure.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/FolderStructure.js
index 771d7742a2d9ce8c74bf492e574f8f8ff3e2aa17..13ef254f6b2269fdfeb28c09dc2ec110be36996d 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/FolderStructure.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/FolderStructure.js
@@ -125,6 +125,9 @@ define(['jquery',
 							$outputContainer.append(message);
 						}
 						self.getStatus();
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/LocalConfiguration.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/LocalConfiguration.js
index 790ea24e2db2b6691274563357d55fc50d0e230e..66e629e98ba51a11bbe891f225eee4332db87c64 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/LocalConfiguration.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/LocalConfiguration.js
@@ -130,6 +130,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.append(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/MailTest.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/MailTest.js
index 3dba7c912f9910d66a7ee097fe1aa3405e48bd80..ce238c9a1b9d0500528adbf1047a9af295f647a8 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/MailTest.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/MailTest.js
@@ -61,6 +61,9 @@ define(['jquery',
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.html(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function () {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/Presets.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/Presets.js
index cdfd37361321bdd6cded5d9753dcb9b44fb1e04f..f570a88e8910f84a3ec2848240d4fed4850fa212 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/Presets.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/Presets.js
@@ -60,6 +60,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 							var message = InfoBox.render(element.severity, element.title, element.message);
 							$outputContainer.append(message);
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ResetBackendUserUc.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ResetBackendUserUc.js
index 34e423cebeed68391e5f9fda69033aab485c68b0..0b4e3ba0dfa97f60baf6667ef0c0d0af7536e669 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/ResetBackendUserUc.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/ResetBackendUserUc.js
@@ -50,6 +50,9 @@ define(['jquery', 'TYPO3/CMS/Install/FlashMessage', 'TYPO3/CMS/Install/ProgressB
 								$outputContainer.append(message);
 							});
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function () {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/SystemMaintainer.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/SystemMaintainer.js
index 8bee9736912cec8cedf0993e84439a51e056a19c..a4e3f328339b9c250fb5e3bc9d4c1ad7dcdd5446 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/SystemMaintainer.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/SystemMaintainer.js
@@ -129,6 +129,9 @@ define([
 								$outputContainer.empty().append(message);
 							});
 						}
+					} else {
+						var message = InfoBox.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaExtTablesCheck.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaExtTablesCheck.js
index 0f5bff16f1bb3097566f663fb684ff6220b31f74..acc7712ecc81377496a98cbfc51794634c320a9d 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaExtTablesCheck.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaExtTablesCheck.js
@@ -65,6 +65,9 @@ define([
 							var message = InfoBox.render(Severity.ok, 'No TCA changes in ext_tables.php files. Good job!', '');
 							$outputContainer.empty().html(message);
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', 'Use "Check for broken extensions"');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaMigrationsCheck.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaMigrationsCheck.js
index 6e28941882cb46c0ce2b8c4af9410127a94f8329..4a068ff08bf10eeadc9333061f9de1a530fb0e08 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaMigrationsCheck.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/TcaMigrationsCheck.js
@@ -65,6 +65,9 @@ define([
 							var message = InfoBox.render(Severity.ok, 'No TCA migrations need to be applied', 'Your TCA looks good.');
 							$outputContainer.empty().html(message);
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', 'Use "Check for broken extensions"');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
diff --git a/typo3/sysext/install/Resources/Public/JavaScript/Modules/UpgradeWizards.js b/typo3/sysext/install/Resources/Public/JavaScript/Modules/UpgradeWizards.js
index 403e0e9b25c7f0614f74820373d8680b7eaff64c..76afe8192ef96aa963a6eac0b86671a0bfc420ae 100644
--- a/typo3/sysext/install/Resources/Public/JavaScript/Modules/UpgradeWizards.js
+++ b/typo3/sysext/install/Resources/Public/JavaScript/Modules/UpgradeWizards.js
@@ -117,6 +117,9 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 							}));
 						}
 						self.blockingUpgradesDatabaseCharsetTest();
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
@@ -176,6 +179,10 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 								$outputContainer.append(message);
 							});
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						self.removeLoadingMessage($outputContainer);
+						$outputContainer.append(message);
 					}
 				},
 				error: function() {
@@ -222,6 +229,10 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 						} else {
 							self.wizardsList();
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						self.removeLoadingMessage($outputContainer);
+						$outputContainer.append(message);
 					}
 				},
 				error: function() {
@@ -253,6 +264,10 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 							});
 							self.wizardsList();
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						self.removeLoadingMessage($outputContainer);
+						$outputContainer.append(message);
 					}
 				},
 				error: function() {
@@ -308,6 +323,10 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 							.find('span')
 							.text(parseInt(percent) + '%');
 						$outputContainer.append(list);
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						self.removeLoadingMessage($outputContainer);
+						$outputContainer.append(message);
 					}
 				},
 				error: function() {
@@ -393,6 +412,9 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 						self.wizardsList();
 						$outputDoneContainer.empty();
 						self.doneUpgrades();
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {
@@ -448,6 +470,10 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 						if (hasBodyContent === true) {
 							$outputContainer.append(body);
 						}
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						self.removeLoadingMessage($outputContainer);
+						$outputContainer.append(message);
 					}
 				},
 				error: function() {
@@ -484,6 +510,9 @@ function($, FlashMessage, ProgressBar, InfoBox, Severity) {
 							self.doneUpgrades();
 							self.blockingUpgradesDatabaseCharsetTest();
 						});
+					} else {
+						var message = FlashMessage.render(Severity.error, 'Something went wrong', '');
+						$outputContainer.empty().html(message);
 					}
 				},
 				error: function() {