diff --git a/apps/updatenotification/lib/ResetTokenBackgroundJob.php b/apps/updatenotification/lib/ResetTokenBackgroundJob.php
index 96a50c5ff7f6d..6e80f0fc0bf76 100644
--- a/apps/updatenotification/lib/ResetTokenBackgroundJob.php
+++ b/apps/updatenotification/lib/ResetTokenBackgroundJob.php
@@ -26,7 +26,7 @@
  */
 namespace OCA\UpdateNotification;
 
-use OC\BackgroundJob\TimedJob;
+use OCP\BackgroundJob\TimedJob;
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\IConfig;
 
@@ -48,8 +48,9 @@ class ResetTokenBackgroundJob extends TimedJob {
 	 */
 	public function __construct(IConfig $config,
 								ITimeFactory $timeFactory) {
+		parent::__construct($timeFactory);
 		// Run all 10 minutes
-		$this->setInterval(60 * 10);
+		parent::setInterval(60 * 10);
 		$this->config = $config;
 		$this->timeFactory = $timeFactory;
 	}
@@ -59,7 +60,7 @@ public function __construct(IConfig $config,
 	 */
 	protected function run($argument) {
 		// Delete old tokens after 2 days
-		if ($this->timeFactory->getTime() - $this->config->getAppValue('core', 'updater.secret.created', $this->timeFactory->getTime()) >= 172800) {
+		if ($this->config->getSystemValueBool('config_is_read_only') === false && $this->timeFactory->getTime() - (int) $this->config->getAppValue('core', 'updater.secret.created', (string) $this->timeFactory->getTime()) >= 172800) {
 			$this->config->deleteSystemValue('updater.secret');
 		}
 	}
diff --git a/apps/updatenotification/tests/ResetTokenBackgroundJobTest.php b/apps/updatenotification/tests/ResetTokenBackgroundJobTest.php
index 129ba37098063..56a82b5b726ab 100644
--- a/apps/updatenotification/tests/ResetTokenBackgroundJobTest.php
+++ b/apps/updatenotification/tests/ResetTokenBackgroundJobTest.php
@@ -56,6 +56,11 @@ public function testRunWithNotExpiredToken() {
 			->expects($this->once())
 			->method('getAppValue')
 			->with('core', 'updater.secret.created', 123);
+		$this->config
+			->expects($this->once())
+			->method('getSystemValueBool')
+			->with('config_is_read_only')
+			->willReturn(false);
 		$this->config
 			->expects($this->never())
 			->method('deleteSystemValue');
@@ -65,13 +70,9 @@ public function testRunWithNotExpiredToken() {
 
 	public function testRunWithExpiredToken() {
 		$this->timeFactory
-			->expects($this->at(0))
+			->expects($this->exactly(2))
 			->method('getTime')
-			->willReturn(1455131633);
-		$this->timeFactory
-			->expects($this->at(1))
-			->method('getTime')
-			->willReturn(1455045234);
+			->willReturnOnConsecutiveCalls(1455131633, 1455045234);
 		$this->config
 			->expects($this->once())
 			->method('getAppValue')
@@ -83,4 +84,23 @@ public function testRunWithExpiredToken() {
 
 		static::invokePrivate($this->resetTokenBackgroundJob, 'run', [null]);
 	}
+
+	public function testRunWithExpiredTokenAndReadOnlyConfigFile() {
+		$this->timeFactory
+			->expects($this->never())
+			->method('getTime');
+		$this->config
+			->expects($this->never())
+			->method('getAppValue');
+		$this->config
+			->expects($this->once())
+			->method('getSystemValueBool')
+			->with('config_is_read_only')
+			->willReturn(true);
+		$this->config
+			->expects($this->never())
+			->method('deleteSystemValue');
+
+		static::invokePrivate($this->resetTokenBackgroundJob, 'run', [null]);
+	}
 }