There was a dangerous problem brought up on Windows Live Writer MSN Group.

Problem:

When you try to publish a post to your blog you are getting this error: “An unexpected error has occured while attempting to log in: Blog Server Error  Server Error -32700 Occured parse error. not well formed”

Solution:

This Problem occures when you use wordpress as your blog software. In fact it is a spam injection to your wordpress installation. This is possible when your wordpress installation or your server isn’t as secure as it should be. Some wordpress files were changed on the server so you getting this error.

To solve this problem, you should replace the files on your server with the original wordpress files of the same version as installed. It looks like the following files are affected:index.php

• xmlrpc.php
• wp-admin/admin.php
• wp-admin/index.php
• wp-includes/wp-db.php
• wp-includes/pluggable.php
• wp-includes/gettext.php
• wp-includes/default-filters.php (critical!)

You also should check your .htaccess file for suspicious redirects and remove them. You have to remove the wp-includes/class-mail.php file. This file does not belong to wordpress and is a security leak.

The server wordpress is installed have to get secure. There is an article on wordpress codex that shows some methods to hardening wordpress.

Further informations:
gordon.dewis.ca
Kakkoi
via Windows Live Writer Group

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