diff --git a/lib/hx509/Makefile.am b/lib/hx509/Makefile.am
index aa7fdfa3a..5f27140cd 100644
--- a/lib/hx509/Makefile.am
+++ b/lib/hx509/Makefile.am
@@ -56,6 +56,7 @@ libhx509_la_files = \
 	cms.c \
 	collector.c \
 	crypto.c \
+	error.c \
 	file.c \
 	hx509.h \
 	keyset.c \