diff --git a/src/Controller/SecurityController.php b/src/Controller/SecurityController.php
index 095dfd54..9f602a80 100644
--- a/src/Controller/SecurityController.php
+++ b/src/Controller/SecurityController.php
@@ -170,7 +170,7 @@ class SecurityController extends AbstractController
                 $this->addFlash('success', 'pw_reset.new_pw.success');
 
                 $repo = $em->getRepository(User::class);
-                $u = $repo->findOneBy(['name' => $data['username']]);
+                $u = $repo->findByUsername($data['username']);
                 $event = new SecurityEvent($u);
                 /** @var EventDispatcher $eventDispatcher */
                 $eventDispatcher->dispatch($event, SecurityEvents::PASSWORD_RESET);
diff --git a/src/DataFixtures/UserFixtures.php b/src/DataFixtures/UserFixtures.php
index 171f671e..d34a83cd 100644
--- a/src/DataFixtures/UserFixtures.php
+++ b/src/DataFixtures/UserFixtures.php
@@ -54,6 +54,7 @@ class UserFixtures extends Fixture implements DependentFixtureInterface
         $user = new User();
         $user->setName('user');
         $user->setNeedPwChange(false);
+        $user->setEmail('user@invalid.invalid');
         $user->setFirstName('Test')->setLastName('User');
         $user->setPassword($this->encoder->hashPassword($user, 'test'));
         $user->setGroup($this->getReference(GroupFixtures::USERS));
@@ -66,6 +67,9 @@ class UserFixtures extends Fixture implements DependentFixtureInterface
         $manager->persist($noread);
 
         $manager->flush();
+
+        //Ensure that the anonymous user has the ID 0
+        $manager->getRepository(User::class)->changeID($anonymous, User::ID_ANONYMOUS);
     }
 
     public function getDependencies(): array
diff --git a/src/Repository/UserRepository.php b/src/Repository/UserRepository.php
index f1e738d0..fa95e83d 100644
--- a/src/Repository/UserRepository.php
+++ b/src/Repository/UserRepository.php
@@ -42,6 +42,7 @@ final class UserRepository extends NamedDBElementRepository implements PasswordU
     /**
      * Returns the anonymous user.
      * The result is cached, so the database is only called once, after the anonymous user was found.
+     * @return User|null The user if it is existing, null if no one matched the criteria
      */
     public function getAnonymousUser(): ?User
     {
@@ -54,6 +55,30 @@ final class UserRepository extends NamedDBElementRepository implements PasswordU
         return $this->anonymous_user;
     }
 
+    /**
+     * Find a user by its username.
+     * @param  string  $username
+     * @return User|null
+     */
+    public function findByUsername(string $username): ?User
+    {
+        if ($username === '') {
+            return null;
+        }
+
+        $qb = $this->createQueryBuilder('u');
+        $qb->select('u')
+            ->where('u.name = (:name)');
+
+        $qb->setParameter('name', $username);
+
+        try {
+            return $qb->getQuery()->getOneOrNullResult();
+        } catch (NonUniqueResultException) {
+            return null;
+        }
+    }
+
     /**
      * Find a user by its name or its email. Useful for login or password reset purposes.
      *
diff --git a/src/Services/UserSystem/PasswordResetManager.php b/src/Services/UserSystem/PasswordResetManager.php
index 2349297b..31dbdf90 100644
--- a/src/Services/UserSystem/PasswordResetManager.php
+++ b/src/Services/UserSystem/PasswordResetManager.php
@@ -97,8 +97,7 @@ class PasswordResetManager
     {
         //Try to find the user
         $repo = $this->em->getRepository(User::class);
-        /** @var User|null $user */
-        $user = $repo->findOneBy(['name' => $username]);
+        $user = $repo->findByUsername($username);
 
         //If no user matching the name, show an error message
         if (!$user instanceof User) {
diff --git a/tests/Repository/UserRepositoryTest.php b/tests/Repository/UserRepositoryTest.php
new file mode 100644
index 00000000..dea4a294
--- /dev/null
+++ b/tests/Repository/UserRepositoryTest.php
@@ -0,0 +1,86 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2023 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace App\Tests\Repository;
+
+use App\Entity\UserSystem\User;
+use App\Repository\UserRepository;
+use PHPUnit\Framework\TestCase;
+use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
+
+class UserRepositoryTest extends WebTestCase
+{
+
+    private $entityManager;
+    /**
+     * @var UserRepository
+     */
+    private $repo;
+
+    protected function setUp(): void
+    {
+        $kernel = self::bootKernel();
+
+        $this->entityManager = $kernel->getContainer()
+            ->get('doctrine')
+            ->getManager();
+
+        $this->repo = $this->entityManager->getRepository(User::class);
+    }
+
+
+    public function testGetAnonymousUser()
+    {
+        $user = $this->repo->getAnonymousUser();
+
+        $this->assertInstanceOf(User::class, $user);
+        $this->assertSame(User::ID_ANONYMOUS, $user->getId());
+        $this->assertSame('anonymous', $user->getUsername());
+    }
+
+    public function testFindByEmailOrName()
+    {
+        //Test for email
+        $u = $this->repo->findByEmailOrName('user@invalid.invalid');
+        $this->assertInstanceOf(User::class, $u);
+        $this->assertSame('user', $u->getUsername());
+
+        //Test for name
+        $u = $this->repo->findByEmailOrName('user');
+        $this->assertInstanceOf(User::class, $u);
+        $this->assertSame('user', $u->getUsername());
+
+        //Check what happens for unknown user
+        $u = $this->repo->findByEmailOrName('unknown');
+        $this->assertNull($u);
+
+    }
+
+    public function testFindByUsername()
+    {
+        $u = $this->repo->findByUsername('user');
+        $this->assertInstanceOf(User::class, $u);
+        $this->assertSame('user', $u->getUsername());
+
+        //Check what happens for unknown user
+        $u = $this->repo->findByEmailOrName('unknown');
+        $this->assertNull($u);
+    }
+}