diff --git a/upload/source/language/lang_message.php b/upload/source/language/lang_message.php
index 603ee089b675d718a1fdbaa03bd9bacebc29e490..10ab473984e82fd6d8b48443117915efa8f0f60d 100644
--- a/upload/source/language/lang_message.php
+++ b/upload/source/language/lang_message.php
@@ -311,6 +311,7 @@ $lang = array (
   'attachment_buyall' => '本帖所有附件购买成功 ',
   'attachment_buy' => '附件购买成功，开始下载“{filename}”',
   'attachment_mobile_buy' => '附件购买成功',
+  'attachment_locked' => '抱歉，由于您所发起的其他附件购买操作正在进行，因此您无法购买当前附件，请稍后再试',
   'no_privilege_postimage' => '抱歉，您目前没有权限上传图片，<a href="home.php?mod=spacecp&ac=usergroup" target="_blank">点击这里查看权限</a>',
   'no_privilege_postattach' => '抱歉，您目前没有权限上传附件，<a href="home.php?mod=spacecp&ac=usergroup" target="_blank">点击这里查看权限</a>',
   'thread_closed' => '该帖子已被关闭，不能评论！',
diff --git a/upload/source/module/forum/forum_misc.php b/upload/source/module/forum/forum_misc.php
index 1234ac6f752ebf25be7abb27f5213f247df13db2..bea8658ca2259b3c8ba748fe093a4600c8a5cda5 100644
--- a/upload/source/module/forum/forum_misc.php
+++ b/upload/source/module/forum/forum_misc.php
@@ -134,6 +134,7 @@ if($_GET['action'] == 'paysucceed') {
 		}
 
 		if($status == 1) {
+			discuz_process::unlock($lockid);
 			showmessage('credits_balance_insufficient', '', array('title' => $_G['setting']['extcredits'][$_G['setting']['creditstransextra'][1]]['title'], 'minbalance' => $attach['price']));
 		}
 		foreach($aids as $aid) {
@@ -166,6 +167,8 @@ if($_GET['action'] == 'paysucceed') {
 				showmessage('attachment_buy', "forum.php?mod=attachment&aid=$aidencode", array('filename' => $_G['forum_attach_filename']), array('redirectmsg' => 1));
 			}
 		}
+	} else {
+		showmessage('attachment_locked');
 	}
 
 } elseif($_GET['action'] == 'viewattachpayments') {