diff --git a/config/container.php b/config/container.php
index 85cb0886..126351ae 100644
--- a/config/container.php
+++ b/config/container.php
@@ -11,7 +11,7 @@ require 'vendor/autoload.php';
 // If the Dotenv class exists, load env vars and enable errors
 if (class_exists(Dotenv::class)) {
     error_reporting(E_ALL);
-    ini_set('display_errors', 1);
+    ini_set('display_errors', '1');
     $dotenv = new Dotenv(__DIR__ . '/..');
     $dotenv->load();
 }
diff --git a/module/CLI/src/Command/Shortcode/ResolveUrlCommand.php b/module/CLI/src/Command/Shortcode/ResolveUrlCommand.php
index e5b53c23..fe79ee16 100644
--- a/module/CLI/src/Command/Shortcode/ResolveUrlCommand.php
+++ b/module/CLI/src/Command/Shortcode/ResolveUrlCommand.php
@@ -3,6 +3,7 @@ declare(strict_types=1);
 
 namespace Shlinkio\Shlink\CLI\Command\Shortcode;
 
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortenerInterface;
 use Symfony\Component\Console\Command\Command;
@@ -81,6 +82,10 @@ class ResolveUrlCommand extends Command
             $output->writeln(sprintf('<error>' . $this->translator->translate(
                 'Provided short code "%s" has an invalid format.'
             ) . '</error>', $shortCode));
+        } catch (EntityDoesNotExistException $e) {
+            $output->writeln(sprintf('<error>' . $this->translator->translate(
+                'Provided short code "%s" could not be found.'
+            ) . '</error>', $shortCode));
         }
     }
 }
diff --git a/module/CLI/test/Command/Shortcode/ResolveUrlCommandTest.php b/module/CLI/test/Command/Shortcode/ResolveUrlCommandTest.php
index c1fef098..da0eadc3 100644
--- a/module/CLI/test/Command/Shortcode/ResolveUrlCommandTest.php
+++ b/module/CLI/test/Command/Shortcode/ResolveUrlCommandTest.php
@@ -6,6 +6,7 @@ namespace ShlinkioTest\Shlink\CLI\Command\Shortcode;
 use PHPUnit\Framework\TestCase;
 use Prophecy\Prophecy\ObjectProphecy;
 use Shlinkio\Shlink\CLI\Command\Shortcode\ResolveUrlCommand;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortener;
 use Symfony\Component\Console\Application;
@@ -57,7 +58,7 @@ class ResolveUrlCommandTest extends TestCase
     public function incorrectShortCodeOutputsErrorMessage()
     {
         $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(null)
+        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(EntityDoesNotExistException::class)
                                                        ->shouldBeCalledTimes(1);
 
         $this->commandTester->execute([
@@ -65,7 +66,7 @@ class ResolveUrlCommandTest extends TestCase
             'shortCode' => $shortCode,
         ]);
         $output = $this->commandTester->getDisplay();
-        $this->assertEquals('No URL found for short code "' . $shortCode . '"' . PHP_EOL, $output);
+        $this->assertEquals('Provided short code "' . $shortCode . '" could not be found.' . PHP_EOL, $output);
     }
 
     /**
diff --git a/module/Core/src/Action/PreviewAction.php b/module/Core/src/Action/PreviewAction.php
index 054da045..788c3c2d 100644
--- a/module/Core/src/Action/PreviewAction.php
+++ b/module/Core/src/Action/PreviewAction.php
@@ -7,8 +7,10 @@ use Interop\Http\ServerMiddleware\DelegateInterface;
 use Interop\Http\ServerMiddleware\MiddlewareInterface;
 use Psr\Http\Message\ResponseInterface as Response;
 use Psr\Http\Message\ServerRequestInterface as Request;
+use Shlinkio\Shlink\Common\Exception\PreviewGenerationException;
 use Shlinkio\Shlink\Common\Service\PreviewGeneratorInterface;
 use Shlinkio\Shlink\Common\Util\ResponseUtilsTrait;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortenerInterface;
 
@@ -46,14 +48,14 @@ class PreviewAction implements MiddlewareInterface
 
         try {
             $url = $this->urlShortener->shortCodeToUrl($shortCode);
-            if (! isset($url)) {
-                return $delegate->process($request);
-            }
-
             $imagePath = $this->previewGenerator->generatePreview($url);
             return $this->generateImageResponse($imagePath);
         } catch (InvalidShortCodeException $e) {
             return $delegate->process($request);
+        } catch (EntityDoesNotExistException $e) {
+            return $delegate->process($request);
+        } catch (PreviewGenerationException $e) {
+            return $delegate->process($request);
         }
     }
 }
diff --git a/module/Core/src/Action/QrCodeAction.php b/module/Core/src/Action/QrCodeAction.php
index a6e20af8..dfd7eaf2 100644
--- a/module/Core/src/Action/QrCodeAction.php
+++ b/module/Core/src/Action/QrCodeAction.php
@@ -11,6 +11,7 @@ use Psr\Http\Message\ServerRequestInterface as Request;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
 use Shlinkio\Shlink\Common\Response\QrCodeResponse;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortenerInterface;
 use Zend\Expressive\Router\RouterInterface;
@@ -55,12 +56,12 @@ class QrCodeAction implements MiddlewareInterface
         $shortCode = $request->getAttribute('shortCode');
         try {
             $shortUrl = $this->urlShortener->shortCodeToUrl($shortCode);
-            if ($shortUrl === null) {
-                return $delegate->process($request);
-            }
         } catch (InvalidShortCodeException $e) {
             $this->logger->warning('Tried to create a QR code with an invalid short code' . PHP_EOL . $e);
             return $delegate->process($request);
+        } catch (EntityDoesNotExistException $e) {
+            $this->logger->warning('Tried to create a QR code with a not found short code' . PHP_EOL . $e);
+            return $delegate->process($request);
         }
 
         $path = $this->router->generateUri('long-url-redirect', ['shortCode' => $shortCode]);
diff --git a/module/Core/src/Action/RedirectAction.php b/module/Core/src/Action/RedirectAction.php
index ae58da1b..c8d35b4a 100644
--- a/module/Core/src/Action/RedirectAction.php
+++ b/module/Core/src/Action/RedirectAction.php
@@ -9,8 +9,11 @@ use Psr\Http\Message\ResponseInterface as Response;
 use Psr\Http\Message\ServerRequestInterface as Request;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
+use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortenerInterface;
 use Shlinkio\Shlink\Core\Service\VisitsTrackerInterface;
+use Zend\Diactoros\Response\HtmlResponse;
 use Zend\Diactoros\Response\RedirectResponse;
 
 class RedirectAction implements MiddlewareInterface
@@ -66,9 +69,9 @@ class RedirectAction implements MiddlewareInterface
             // Return a redirect response to the long URL.
             // Use a temporary redirect to make sure browsers always hit the server for analytics purposes
             return new RedirectResponse($longUrl);
-        } catch (\Exception $e) {
-            // In case of error, dispatch 404 error
-            $this->logger->error('Error redirecting to long URL.' . PHP_EOL . $e);
+        } catch (InvalidShortCodeException $e) {
+            return $delegate->process($request);
+        } catch (EntityDoesNotExistException $e) {
             return $delegate->process($request);
         }
     }
diff --git a/module/Core/src/Service/UrlShortener.php b/module/Core/src/Service/UrlShortener.php
index df4ee8ed..b30b649a 100644
--- a/module/Core/src/Service/UrlShortener.php
+++ b/module/Core/src/Service/UrlShortener.php
@@ -11,6 +11,7 @@ use GuzzleHttp\Exception\GuzzleException;
 use Psr\Http\Message\UriInterface;
 use Shlinkio\Shlink\Common\Exception\RuntimeException;
 use Shlinkio\Shlink\Core\Entity\ShortUrl;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Exception\InvalidUrlException;
 use Shlinkio\Shlink\Core\Util\TagManagerTrait;
@@ -142,10 +143,11 @@ class UrlShortener implements UrlShortenerInterface
      * Tries to find the mapped URL for provided short code. Returns null if not found
      *
      * @param string $shortCode
-     * @return string|null
+     * @return string
      * @throws InvalidShortCodeException
+     * @throws EntityDoesNotExistException
      */
-    public function shortCodeToUrl($shortCode)
+    public function shortCodeToUrl($shortCode): string
     {
         $cacheKey = sprintf('%s_longUrl', $shortCode);
         // Check if the short code => URL map is already cached
@@ -158,17 +160,16 @@ class UrlShortener implements UrlShortenerInterface
             throw InvalidShortCodeException::fromCharset($shortCode, $this->chars);
         }
 
-        /** @var ShortUrl $shortUrl */
-        $shortUrl = $this->em->getRepository(ShortUrl::class)->findOneBy([
-            'shortCode' => $shortCode,
-        ]);
-        // Cache the shortcode
-        if (isset($shortUrl)) {
-            $url = $shortUrl->getOriginalUrl();
-            $this->cache->save($cacheKey, $url);
-            return $url;
+        $criteria = ['shortCode' => $shortCode];
+        /** @var ShortUrl|null $shortUrl */
+        $shortUrl = $this->em->getRepository(ShortUrl::class)->findOneBy($criteria);
+        if ($shortUrl === null) {
+            throw EntityDoesNotExistException::createFromEntityAndConditions(ShortUrl::class, $criteria);
         }
 
-        return null;
+        // Cache the shortcode
+        $url = $shortUrl->getOriginalUrl();
+        $this->cache->save($cacheKey, $url);
+        return $url;
     }
 }
diff --git a/module/Core/src/Service/UrlShortenerInterface.php b/module/Core/src/Service/UrlShortenerInterface.php
index c677ec4e..3cd2c35c 100644
--- a/module/Core/src/Service/UrlShortenerInterface.php
+++ b/module/Core/src/Service/UrlShortenerInterface.php
@@ -5,6 +5,7 @@ namespace Shlinkio\Shlink\Core\Service;
 
 use Psr\Http\Message\UriInterface;
 use Shlinkio\Shlink\Common\Exception\RuntimeException;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Exception\InvalidUrlException;
 
@@ -25,8 +26,9 @@ interface UrlShortenerInterface
      * Tries to find the mapped URL for provided short code. Returns null if not found
      *
      * @param string $shortCode
-     * @return string|null
+     * @return string
      * @throws InvalidShortCodeException
+     * @throws EntityDoesNotExistException
      */
-    public function shortCodeToUrl($shortCode);
+    public function shortCodeToUrl($shortCode): string;
 }
diff --git a/module/Core/test/Action/PreviewActionTest.php b/module/Core/test/Action/PreviewActionTest.php
index 5521e677..d791a100 100644
--- a/module/Core/test/Action/PreviewActionTest.php
+++ b/module/Core/test/Action/PreviewActionTest.php
@@ -9,6 +9,7 @@ use Prophecy\Argument;
 use Prophecy\Prophecy\ObjectProphecy;
 use Shlinkio\Shlink\Common\Service\PreviewGenerator;
 use Shlinkio\Shlink\Core\Action\PreviewAction;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortener;
 use ShlinkioTest\Shlink\Common\Util\TestUtils;
@@ -42,7 +43,8 @@ class PreviewActionTest extends TestCase
     public function invalidShortCodeFallsBackToNextMiddleware()
     {
         $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(null)->shouldBeCalledTimes(1);
+        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(EntityDoesNotExistException::class)
+                                                       ->shouldBeCalledTimes(1);
         $delegate = $this->prophesize(DelegateInterface::class);
         $delegate->process(Argument::cetera())->shouldBeCalledTimes(1);
 
diff --git a/module/Core/test/Action/QrCodeActionTest.php b/module/Core/test/Action/QrCodeActionTest.php
index 85f908e2..ba8adc2f 100644
--- a/module/Core/test/Action/QrCodeActionTest.php
+++ b/module/Core/test/Action/QrCodeActionTest.php
@@ -10,6 +10,7 @@ use Prophecy\Prophecy\ObjectProphecy;
 use Shlinkio\Shlink\Common\Response\QrCodeResponse;
 use Shlinkio\Shlink\Core\Action\QrCodeAction;
 use Shlinkio\Shlink\Core\Entity\ShortUrl;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortener;
 use Zend\Diactoros\ServerRequestFactory;
@@ -42,7 +43,8 @@ class QrCodeActionTest extends TestCase
     public function aNotFoundShortCodeWillDelegateIntoNextMiddleware()
     {
         $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(null)->shouldBeCalledTimes(1);
+        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(EntityDoesNotExistException::class)
+                                                       ->shouldBeCalledTimes(1);
         $delegate = $this->prophesize(DelegateInterface::class);
 
         $this->action->process(
@@ -77,7 +79,7 @@ class QrCodeActionTest extends TestCase
     public function aCorrectRequestReturnsTheQrCodeResponse()
     {
         $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(new ShortUrl())->shouldBeCalledTimes(1);
+        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn('')->shouldBeCalledTimes(1);
         $delegate = $this->prophesize(DelegateInterface::class);
 
         $resp = $this->action->process(
diff --git a/module/Core/test/Action/RedirectActionTest.php b/module/Core/test/Action/RedirectActionTest.php
index e2cc700a..49d3baec 100644
--- a/module/Core/test/Action/RedirectActionTest.php
+++ b/module/Core/test/Action/RedirectActionTest.php
@@ -8,6 +8,7 @@ use PHPUnit\Framework\TestCase;
 use Prophecy\Argument;
 use Prophecy\Prophecy\ObjectProphecy;
 use Shlinkio\Shlink\Core\Action\RedirectAction;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Service\UrlShortener;
 use Shlinkio\Shlink\Core\Service\VisitsTracker;
 use ShlinkioTest\Shlink\Common\Util\TestUtils;
@@ -58,23 +59,7 @@ class RedirectActionTest extends TestCase
     public function nextMiddlewareIsInvokedIfLongUrlIsNotFound()
     {
         $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(null)
-                           ->shouldBeCalledTimes(1);
-        $delegate = $this->prophesize(DelegateInterface::class);
-
-        $request = ServerRequestFactory::fromGlobals()->withAttribute('shortCode', $shortCode);
-        $this->action->process($request, $delegate->reveal());
-
-        $delegate->process($request)->shouldHaveBeenCalledTimes(1);
-    }
-
-    /**
-     * @test
-     */
-    public function nextMiddlewareIsInvokedIfAnExceptionIsThrown()
-    {
-        $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(\Exception::class)
+        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(EntityDoesNotExistException::class)
                                                        ->shouldBeCalledTimes(1);
         $delegate = $this->prophesize(DelegateInterface::class);
 
diff --git a/module/Rest/src/Action/ResolveUrlAction.php b/module/Rest/src/Action/ResolveUrlAction.php
index f20d4222..1abf5626 100644
--- a/module/Rest/src/Action/ResolveUrlAction.php
+++ b/module/Rest/src/Action/ResolveUrlAction.php
@@ -7,6 +7,7 @@ use Interop\Http\ServerMiddleware\DelegateInterface;
 use Psr\Http\Message\ResponseInterface as Response;
 use Psr\Http\Message\ServerRequestInterface as Request;
 use Psr\Log\LoggerInterface;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortenerInterface;
 use Shlinkio\Shlink\Rest\Util\RestUtils;
@@ -46,13 +47,6 @@ class ResolveUrlAction extends AbstractRestAction
 
         try {
             $longUrl = $this->urlShortener->shortCodeToUrl($shortCode);
-            if ($longUrl === null) {
-                return new JsonResponse([
-                    'error' => RestUtils::INVALID_ARGUMENT_ERROR,
-                    'message' => sprintf($this->translator->translate('No URL found for short code "%s"'), $shortCode),
-                ], self::STATUS_NOT_FOUND);
-            }
-
             return new JsonResponse([
                 'longUrl' => $longUrl,
             ]);
@@ -65,6 +59,12 @@ class ResolveUrlAction extends AbstractRestAction
                     $shortCode
                 ),
             ], self::STATUS_BAD_REQUEST);
+        } catch (EntityDoesNotExistException $e) {
+            $this->logger->warning('Provided short code couldn\'t be found.' . PHP_EOL . $e);
+            return new JsonResponse([
+                'error' => RestUtils::INVALID_ARGUMENT_ERROR,
+                'message' => sprintf($this->translator->translate('No URL found for short code "%s"'), $shortCode),
+            ], self::STATUS_NOT_FOUND);
         } catch (\Exception $e) {
             $this->logger->error('Unexpected error while resolving the URL behind a short code.' . PHP_EOL . $e);
             return new JsonResponse([
diff --git a/module/Rest/test/Action/ResolveUrlActionTest.php b/module/Rest/test/Action/ResolveUrlActionTest.php
index 48c17b20..884fae55 100644
--- a/module/Rest/test/Action/ResolveUrlActionTest.php
+++ b/module/Rest/test/Action/ResolveUrlActionTest.php
@@ -5,6 +5,7 @@ namespace ShlinkioTest\Shlink\Rest\Action;
 
 use PHPUnit\Framework\TestCase;
 use Prophecy\Prophecy\ObjectProphecy;
+use Shlinkio\Shlink\Core\Exception\EntityDoesNotExistException;
 use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
 use Shlinkio\Shlink\Core\Service\UrlShortener;
 use Shlinkio\Shlink\Rest\Action\ResolveUrlAction;
@@ -36,7 +37,7 @@ class ResolveUrlActionTest extends TestCase
     public function incorrectShortCodeReturnsError()
     {
         $shortCode = 'abc123';
-        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(null)
+        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(EntityDoesNotExistException::class)
                                                        ->shouldBeCalledTimes(1);
 
         $request = ServerRequestFactory::fromGlobals()->withAttribute('shortCode', $shortCode);