diff --git a/apps/dav/lib/Connector/PublicAuth.php b/apps/dav/lib/Connector/PublicAuth.php
index cc51a249e7570..fb952a8a99518 100644
--- a/apps/dav/lib/Connector/PublicAuth.php
+++ b/apps/dav/lib/Connector/PublicAuth.php
@@ -61,7 +61,7 @@ public function __construct(IRequest $request,
 
 		// setup realm
 		$defaults = new \OCP\Defaults();
-		$this->realm = $defaults->getName();
+		$this->realm = $defaults->getName() ?: 'Nextcloud';
 	}
 
 	/**
diff --git a/apps/dav/lib/Connector/Sabre/Auth.php b/apps/dav/lib/Connector/Sabre/Auth.php
index 69e3946bb1152..d0c309651cd2a 100644
--- a/apps/dav/lib/Connector/Sabre/Auth.php
+++ b/apps/dav/lib/Connector/Sabre/Auth.php
@@ -76,7 +76,7 @@ public function __construct(ISession $session,
 
 		// setup realm
 		$defaults = new \OCP\Defaults();
-		$this->realm = $defaults->getName();
+		$this->realm = $defaults->getName() ?: 'Nextcloud';
 	}
 
 	/**
diff --git a/apps/dav/lib/Connector/Sabre/BearerAuth.php b/apps/dav/lib/Connector/Sabre/BearerAuth.php
index 5a69d07b0026d..b38600bd94431 100644
--- a/apps/dav/lib/Connector/Sabre/BearerAuth.php
+++ b/apps/dav/lib/Connector/Sabre/BearerAuth.php
@@ -47,7 +47,7 @@ public function __construct(IUserSession $userSession,
 
 		// setup realm
 		$defaults = new \OCP\Defaults();
-		$this->realm = $defaults->getName();
+		$this->realm = $defaults->getName() ?: 'Nextcloud';
 	}
 
 	private function setupUserFs($userId) {