I have setup the wordpress blog and it was working fine until last night. But today, I can navigate my blog without any issue. I can create a post without any problems and autosave works fine. But when I publish the post it throws the error message: can not publish a post.
1) Disable all the plugins and enable it one by one to find out the culprit.
2) Upgrade your wordpress to the latest version
3) Add this code in htaccess of your blog and have a check with publishing a post: