On my blog, I’ve recently posted an article on how to solve many of these problems by first identifying them precisely using either the log file of WLW and/or an HTML traffic capturing tool such as Fiddler. Beside the log file and Fiddler, this article also covers in detail some of the most common problems such a the presence of an UTF-8 BOM at the beginning of one of the PHP script files or the presence of extraneous characters at either the beginning (before the opening tag ) of one of those PHP script files.

You can find this article there:

http://coding-paparazzi.sylvainlafontaine.com/2010/02/solving-connection-problems-wlw.html

In the second part (soon to be published), I will cover the problem of the presence of Warning and of Fatal PHP error messages in the XML-RPC response file. Fatal errors are usually the result of some kind of error in the PHP code but you can get a Warning error message simply by having a badly set php.ini file; so it’s often simply a local configuration problem of PHP.

Please help. I love live writer and hate not being able to post to my wordpress 2.6 blog anymore.

There is an error in some versions of xmlrpc.php.

In function mw_newPost()
this line about halfway in the function is incorrect, and will show up in the log of the latest version of Windows Live Writer.

logIO(’O’, ‘Post cats: ‘ . printr($catnames,true));

printr is not a PHP function nor is it defined in the WordPress code.

Instead of “printr”, the correct function name is “print_r”

logIO(’O’, ‘Post cats: ‘ . print_r($catnames,true));