diff --git a/src/Util/PackageFinder.php b/src/Util/PackageFinder.php
index 0a1665a..91d824a 100644
--- a/src/Util/PackageFinder.php
+++ b/src/Util/PackageFinder.php
@@ -84,7 +84,7 @@ public function findPathOf(PackageInterface $package): string
     {
         $path = $this->installationManager->getInstallPath($package);
 
-        return $this->filesystem->normalizePath($path);
+        return is_string($path) ? $this->filesystem->normalizePath($path) : '';
     }
 
     /**