diff --git a/core/runtime/src/main/java/io/quarkus/runtime/configuration/ConfigDiagnostic.java b/core/runtime/src/main/java/io/quarkus/runtime/configuration/ConfigDiagnostic.java
index 41d698b81a3d1..574ae74cf169e 100644
--- a/core/runtime/src/main/java/io/quarkus/runtime/configuration/ConfigDiagnostic.java
+++ b/core/runtime/src/main/java/io/quarkus/runtime/configuration/ConfigDiagnostic.java
@@ -184,7 +184,7 @@ public static Set<String> configFiles(Path configFilesLocation) throws IOExcepti
         Set<String> configFiles = new HashSet<>();
         try (DirectoryStream<Path> candidates = Files.newDirectoryStream(configFilesLocation, CONFIG_FILES_FILTER)) {
             for (Path candidate : candidates) {
-                configFiles.add(candidate.toUri().getPath());
+                configFiles.add(candidate.toUri().toURL().toString());
             }
         }
         return configFiles;