diff --git a/src/ap/ap_config.c b/src/ap/ap_config.c
index 20be2d47e..fbedb6294 100644
--- a/src/ap/ap_config.c
+++ b/src/ap/ap_config.c
@@ -566,15 +566,15 @@ hostapd_get_eap_user(const struct hostapd_bss_config *conf, const u8 *identity,
 		return &wsc_enrollee;
 	}
 
-	if (conf->wps_state && conf->ap_pin &&
-	    identity_len == WSC_ID_REGISTRAR_LEN &&
+	if (conf->wps_state && identity_len == WSC_ID_REGISTRAR_LEN &&
 	    os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0) {
 		static struct hostapd_eap_user wsc_registrar;
 		os_memset(&wsc_registrar, 0, sizeof(wsc_registrar));
 		wsc_registrar.methods[0].method = eap_server_get_type(
 			"WSC", &wsc_registrar.methods[0].vendor);
 		wsc_registrar.password = (u8 *) conf->ap_pin;
-		wsc_registrar.password_len = os_strlen(conf->ap_pin);
+		wsc_registrar.password_len = conf->ap_pin ?
+			os_strlen(conf->ap_pin) : 0;
 		return &wsc_registrar;
 	}
 #endif /* CONFIG_WPS */
diff --git a/src/ap/wps_hostapd.c b/src/ap/wps_hostapd.c
index 902a65aca..c63b7fc89 100644
--- a/src/ap/wps_hostapd.c
+++ b/src/ap/wps_hostapd.c
@@ -426,7 +426,7 @@ static void hostapd_pwd_auth_fail(struct hostapd_data *hapd,
 {
 	FILE *f;
 
-	if (!data->enrollee)
+	if (!data->enrollee || hapd->conf->ap_pin == NULL)
 		return;
 
 	/*
diff --git a/src/eap_server/eap_server_wsc.c b/src/eap_server/eap_server_wsc.c
index 272a6195b..28d4f67dd 100644
--- a/src/eap_server/eap_server_wsc.c
+++ b/src/eap_server/eap_server_wsc.c
@@ -119,10 +119,15 @@ static void * eap_wsc_init(struct eap_sm *sm)
 		}
 	} else {
 		if (sm->user == NULL || sm->user->password == NULL) {
-			wpa_printf(MSG_INFO, "EAP-WSC: No AP PIN (password) "
-				   "configured for Enrollee functionality");
-			os_free(data);
-			return NULL;
+			/*
+			 * In theory, this should not really be needed, but
+			 * Windows 7 uses Registrar mode to probe AP's WPS
+			 * capabilities before trying to use Enrollee and fails
+			 * if the AP does not allow that probing to happen..
+			 */
+			wpa_printf(MSG_DEBUG, "EAP-WSC: No AP PIN (password) "
+				   "configured for Enrollee functionality - "
+				   "allow for probing capabilities (M1)");
 		}
 		cfg.pin = sm->user->password;
 		cfg.pin_len = sm->user->password_len;
diff --git a/src/wps/wps_upnp_web.c b/src/wps/wps_upnp_web.c
index 2e60607e8..9a6b36e02 100644
--- a/src/wps/wps_upnp_web.c
+++ b/src/wps/wps_upnp_web.c
@@ -412,6 +412,9 @@ web_process_get_device_info(struct upnp_wps_device_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "WPS UPnP: GetDeviceInfo");
 
+	if (sm->ctx->ap_pin == NULL)
+		return HTTP_INTERNAL_SERVER_ERROR;
+
 	/*
 	 * Request for DeviceInfo, i.e., M1 TLVs. This is a start of WPS
 	 * registration over UPnP with the AP acting as an Enrollee. It should