edit

sdk/wechat/WxPay.Config.php

@@ -33,7 +33,7 @@ class WxPayConfig
 	}
 	public function GetSignType()
 	{
-		return "HMAC-SHA256";
+		return "MD5";
 	}
 	public function GetProxy(&$proxyHost, &$proxyPort)
 	{