diff --git a/app/controllers/concerns/git_helper.rb b/app/controllers/concerns/git_helper.rb
index ec0f2ad82..abedd4dda 100644
--- a/app/controllers/concerns/git_helper.rb
+++ b/app/controllers/concerns/git_helper.rb
@@ -13,7 +13,7 @@ module GitHelper
 
       content = GitService.file_content(repo_path: repo_path, path: path)
 
-      Rails.logger.info("git file content: content is #{content}")
+      #Rails.logger.info("git file content: content is #{content}")
       decode_content = nil
       if content.present?
         content = content["content"]   #6.24 -hs 这个为新增，因为当实训题里含有选择题时，这里会报错,undefined method `[]' for nil:NilClass
@@ -26,7 +26,7 @@ module GitHelper
             if cd["encoding"] == 'GB18030' && cd['confidence'] > 0.8
               content.encode('UTF-8', 'GBK', {:invalid => :replace, :undef => :replace, :replace => ' '})
             elsif cd['encoding'].blank?
-              raise("无效的utf-8文件")
+              raise("ERROR_UTF8")
             else
               Rails.logger.info("####encoding:#{content.encoding}")
               content.force_encoding('UTF-8')
@@ -37,7 +37,8 @@ module GitHelper
 
     rescue Exception => e
       Rails.logger.error(e.message)
-      raise Educoder::TipException.new("文档内容获取异常")
+      error_msg = e.message == "ERROR_UTF8" ? "文件无法预览" : "文档内容获取异常"
+      raise Educoder::TipException.new(error_msg)
     end
   end