Unable to upload images

My blog is https://www.tarumatu.com, since last night i’m unable to upload images to the media library, a ‘http error’ appears on the flash uploader. I’ve checked my disc usage and i have over 100Mb spare for uploading files, so no issues there. If i use the browser uploader, i get a new page which says ‘Not found. Sorry, there is nothing to post. Please try another search.’

I’m able to create and publish posts, just not able to upload. Can you help.