I just finished an uber-frustrating round of troubleshooting on this site and really don't have a good answer other than 'Don't post that one.' For reasons I completely fail to understand a post I composed at work was triggering a 403 error every time I tried to post it regardless of whether I used the web interface or XMLRPC to post it. I assumed (from the error) that something was colossally fucked with my server configuration.
Nope. It was the post. Any of y'all ever seen defects like this? I read back through the post and made sure all of my brackets were closed and what not but even some syntax highlighting text editor perusal failed to bring anything that broken to my attention. I'll probably figure it out mere minutes after posting this..