diff --git a/src/os/win32/win32_sigar.c b/src/os/win32/win32_sigar.c
index ecfce176..563e3e89 100644
--- a/src/os/win32/win32_sigar.c
+++ b/src/os/win32/win32_sigar.c
@@ -257,6 +257,7 @@ int sigar_os_open(sigar_t **sigar)
         (*sigar)->ip_handle = h;
     }
     else {
+        (*sigar)->get_if_entry = NULL;
         (*sigar)->get_if_table = NULL;
         (*sigar)->get_ipforward_table = NULL;
         (*sigar)->ip_handle = NULL;