Whilst I was helping out Bookninja earlier this week, I came across a strange problem in WordPress.
Every time we tried to publish a new blog post (or page), there would be a pause, then the page would go blank.
(This was on the “post.php” page)
I spent a long time trying to figure out what the issue was… even longer googling it!
Several pages into the Google results, I found the answer! Thank you Sean Deasy!
WordPress posting issue solved at last 
It seems that Bookninja’s hijacker added a rogue URL to the notification/ping-list (http://www.newsisfree.com/RPCCloud), who knows why it was put there, but it was definitely the cause of the blank “post.php” issue!
After removing the rogue URL, everything was working fine again!
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Hi Lee,
Just came across this post on how my post helped you sort that problem out. Glad that it helped you.
- Sean
I too struggled with this issue as well and found Microsoft Live Writer brought up a error connection error each time I tried to post.
Found the ping http://api.feedster.com/ping was my issue.
Apart from problem with comments, people can also get a blank page on commenting because some of their comments are marked as spam by blog owners. Akismet sends a 403 error along with blank page in this case. You might want to check that out.
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