diff --git a/lib/Horde/Core/ActiveSync/Connector.php b/lib/Horde/Core/ActiveSync/Connector.php
index 922182b4..09ecbfba 100644
--- a/lib/Horde/Core/ActiveSync/Connector.php
+++ b/lib/Horde/Core/ActiveSync/Connector.php
@@ -456,6 +456,12 @@ public function getRecipientCache($max = 100)
      */
     public function contacts_search($query, array $options = [])
     {
+        // IMP can advertise contacts/favouriteRecipients without a full contacts
+        // provider (Turba). hasInterface('contacts') is false in that case.
+        if (!$this->_registry->hasInterface('contacts')) {
+            return [];
+        }
+
         if ((!$gal = $this->contacts_getGal()) && empty($options['recipient_cache_search'])) {
             return [];
         }
@@ -522,6 +528,10 @@ public function resolveRecipient($query, array $opts = [])
             }
         }
 
+        if (!$this->_registry->hasInterface('contacts')) {
+            return [$query => []];
+        }
+
         $gal = $this->contacts_getGal();
         $sources = array_keys($this->_registry->contacts->sources(false, true));
         if (!in_array($gal, $sources)) {
@@ -556,8 +566,14 @@ public function resolveRecipient($query, array $opts = [])
      */
     public function contacts_getGal()
     {
-        if (empty($this->_gal)) {
-            $this->_gal = $this->_registry->contacts->getGalUid();
+        if (!isset($this->_gal)) {
+            // Avoid $registry->contacts->getGalUid() when no contacts provider
+            // is registered. listAPIs() may still list "contacts" because IMP
+            // provides contacts/favouriteRecipients, which makes __get('contacts')
+            // succeed and then call() throw for getGalUid.
+            $this->_gal = $this->_registry->hasMethod('contacts/getGalUid')
+                ? $this->_registry->contacts->getGalUid()
+                : false;
         }
         return $this->_gal;
     }
diff --git a/test/Unit/ActiveSync/ConnectorContactsGetGalTest.php b/test/Unit/ActiveSync/ConnectorContactsGetGalTest.php
new file mode 100644
index 00000000..fad0d086
--- /dev/null
+++ b/test/Unit/ActiveSync/ConnectorContactsGetGalTest.php
@@ -0,0 +1,118 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @author Torben Dannhauer <torben@dannhauer.de>
+ * @category Horde
+ * @copyright 2026 The Horde Project
+ * @license http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @package Core
+ * @subpackage UnitTests
+ */
+
+namespace Horde\Core\Test\Unit\ActiveSync;
+
+use Horde_Core_ActiveSync_Connector;
+use Horde_Registry;
+use PHPUnit\Framework\Attributes\CoversMethod;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Unit tests for Horde_Core_ActiveSync_Connector contacts helpers without Turba.
+ */
+#[CoversMethod(Horde_Core_ActiveSync_Connector::class, 'contacts_getGal')]
+#[CoversMethod(Horde_Core_ActiveSync_Connector::class, 'contacts_search')]
+#[CoversMethod(Horde_Core_ActiveSync_Connector::class, 'resolveRecipient')]
+class ConnectorContactsGetGalTest extends TestCase
+{
+    public function testContactsGetGalReturnsFalseWhenMethodMissing(): void
+    {
+        $registry = $this->createMock(Horde_Registry::class);
+        $registry->expects($this->once())
+            ->method('hasMethod')
+            ->with('contacts/getGalUid')
+            ->willReturn(false);
+        $registry->expects($this->never())
+            ->method('__get');
+
+        $connector = new Horde_Core_ActiveSync_Connector([
+            'registry' => $registry,
+        ]);
+
+        $this->assertFalse($connector->contacts_getGal());
+        // Cached: second call must not hit the registry again.
+        $this->assertFalse($connector->contacts_getGal());
+    }
+
+    public function testContactsGetGalReturnsUidWhenAvailable(): void
+    {
+        $contacts = new class () {
+            public function getGalUid()
+            {
+                return 'gal-source';
+            }
+        };
+
+        $registry = $this->createMock(Horde_Registry::class);
+        $registry->expects($this->once())
+            ->method('hasMethod')
+            ->with('contacts/getGalUid')
+            ->willReturn(true);
+        $registry->expects($this->once())
+            ->method('__get')
+            ->with('contacts')
+            ->willReturn($contacts);
+
+        $connector = new Horde_Core_ActiveSync_Connector([
+            'registry' => $registry,
+        ]);
+
+        $this->assertSame('gal-source', $connector->contacts_getGal());
+        $this->assertSame('gal-source', $connector->contacts_getGal());
+    }
+
+    public function testContactsSearchReturnsEmptyWithoutContactsInterface(): void
+    {
+        $registry = $this->createMock(Horde_Registry::class);
+        $registry->expects($this->once())
+            ->method('hasInterface')
+            ->with('contacts')
+            ->willReturn(false);
+        $registry->expects($this->never())
+            ->method('hasMethod');
+        $registry->expects($this->never())
+            ->method('__get');
+
+        $connector = new Horde_Core_ActiveSync_Connector([
+            'registry' => $registry,
+        ]);
+
+        $this->assertSame([], $connector->contacts_search('alice'));
+    }
+
+    public function testResolveRecipientReturnsEmptyWithoutContactsInterface(): void
+    {
+        $registry = $this->createMock(Horde_Registry::class);
+        $registry->expects($this->once())
+            ->method('hasInterface')
+            ->with('contacts')
+            ->willReturn(false);
+        $registry->expects($this->never())
+            ->method('__get');
+
+        $connector = new Horde_Core_ActiveSync_Connector([
+            'registry' => $registry,
+        ]);
+
+        $this->assertSame(
+            ['alice@example.com' => []],
+            $connector->resolveRecipient('alice@example.com')
+        );
+    }
+}