diff --git a/source/packages/com_mokosuitebackup/src/Engine/BackupEngine.php b/source/packages/com_mokosuitebackup/src/Engine/BackupEngine.php
index bf6544d..fa4a143 100644
--- a/source/packages/com_mokosuitebackup/src/Engine/BackupEngine.php
+++ b/source/packages/com_mokosuitebackup/src/Engine/BackupEngine.php
@@ -381,14 +381,19 @@ class BackupEngine
 	 */
 	private function checkRequiredExtensions(): true|string
 	{
+		$required = [
+			'zip'       => 'ext-zip (required for archive creation)',
+			'pdo'       => 'ext-pdo (required for database operations)',
+			'pdo_mysql' => 'ext-pdo_mysql (required for MySQL database dumps)',
+			'mbstring'  => 'ext-mbstring (required for binary-safe operations)',
+		];
+
 		$missing = [];
 
-		if (!extension_loaded('zip')) {
-			$missing[] = 'ext-zip (required for archive creation)';
-		}
-
-		if (!extension_loaded('mbstring') && !function_exists('mb_strlen')) {
-			$missing[] = 'ext-mbstring (required for binary-safe operations)';
+		foreach ($required as $ext => $label) {
+			if (!extension_loaded($ext)) {
+				$missing[] = $label;
+			}
 		}
 
 		if (!empty($missing)) {
diff --git a/source/script.php b/source/script.php
index f194511..4964a31 100644
--- a/source/script.php
+++ b/source/script.php
@@ -58,6 +58,19 @@ class Pkg_MokoSuiteBackupInstallerScript
 			return false;
 		}
 
+		// Check required PHP extensions (warn but don't block install)
+		$requiredExts = ['zip', 'pdo', 'pdo_mysql', 'mbstring', 'curl'];
+		$missingExts  = array_filter($requiredExts, fn($ext) => !extension_loaded($ext));
+
+		if (!empty($missingExts)) {
+			Factory::getApplication()->enqueueMessage(
+				'<strong>MokoSuiteBackup — Missing PHP Extensions</strong>: '
+				. implode(', ', array_map(fn($e) => 'ext-' . $e, $missingExts))
+				. '. Some features (backup, restore, remote upload, notifications) may not work until these are enabled.',
+				'warning'
+			);
+		}
+
 		// Save download key before Joomla re-registers the update site
 		if ($type === 'update') {
 			$this->preflight_saveKey();