diff --git a/src/identity-challenge/challenge-credential.cpp b/src/identity-challenge/challenge-credential.cpp
index da47469..5ec176b 100644
--- a/src/identity-challenge/challenge-credential.cpp
+++ b/src/identity-challenge/challenge-credential.cpp
@@ -37,7 +37,7 @@
     : ChallengeModule("Credential", 1, time::seconds(1))
 {
   if (configPath.empty()) {
-    m_configFile = std::string(SYSCONFDIR) + "/ndncert/challenge-credential.conf";
+    m_configFile = std::string(NDNCERT_SYSCONFDIR) + "/ndncert/challenge-credential.conf";
   }
   else {
     m_configFile = configPath;