Reupload wordpress files to solve live writer connection problem

When WLW(2008version) connecting to wordpress 2.3.1, it returned this error:

尝试连接到日志时出错:
服务器响应无效-从日志服务器接收的对blogger.getUsersBlogs方法的响应无效():
Invalid response documnet returned from XmlRpc server
必须先纠正此错误才能继续操作

the English version is:

Error connecting to weblog

An error occurred while attempting to connect to your weblog;
invalid server resonse -the response to the bloger.getuserblogs method received form weblog server was invalid;
Invalid response document returned from xmlrpc server
You must correct this error before proceeding

I spent 2 days to looking for the solution. modify the .htaccess file, remove the blank near closing tag, use the default theme and deactivate all plugins, all those action did not work at all. Before contacting with my blog’s host, I delated all the wordpress files on the ftp but didnot clear the database and reuploaded, and then succeed! of course backup before that.

btw: before solving the problem, I have used fiddler to see what happened, and it returned a mismatch error:

Content-Length mismatch: Response Header claimed 531 bytes, but server sent 2938 bytes.

I don’t know why.