I just updgraded to 2.6, and something very odd is happening. I use Windows Live Writer. I can post to any of my secondary sites just fine. But, when I post to my main site at http://www.r180.com/blog, I get an error.
The post does show up, but the error shows nonetheless. "The server reported an error with the following URL: http://www.r180.com/blog/xmlrpc.php
500 Internal Server Error
Then, I can't delete the post from WLW. If I hit 'publish' again, it sends a 2nd post instead of overwriting the first one. And, the error pops up again.
What could be wrong?
I have had the same problem since upgrading to 2.6.1 I have checked that API and xmlrpc are enabled in settings but it makes no difference.
The problem only occurs when trying to publish posts with images I am trying to upload so I assume it's the upload issue many have had but I have not yet found a solution - linking to pre-hosted images works fine but I don't consider that a fix lol
I'm experiencing problems with livewriter and WPMU 2.6x as well-- never had any problems, now it detects the blog but says I don't have an active blog... but of course I do!
I was getting the 500 Internal Server Error due to the data type of the post_parent column in the wp_posts table. Here are the details and how I fixed it:
http://ardentdev.com/fix-for-wordpress-xmlrpc-500-internal-server-error/