can anyone tell me that what does it means "wp-comments-post.php" actually while posting the comment after click on the submit button the screen goes white and in url wp-comments-post.php added. what does it means can anyone help me out?
It is probably a problem with the theme you chose or a plugin. What is your URL and/or the theme you are using? did you install a specific plugin to manage comments?
definitely sounds like something is wrong with the generic code. Try just reverting back to the default theme and adding a comment. See if the problem still happens, if it doesn't. then its a problem with your theme. If it still happens then the core code of your Wordpress might have altered and you may need to uninstall it and try again
It means your comments are being flagged as spam. Most likely Akismet is the cause. Additional info at: http://searchengineoptimizationplus.com/2008/09/15/submit-blog-comments-and-getting-a-blank-page/
that's right. akismet is a wordpress plugin. as i know when some blogs reports your comments as a spam, akismet include your url to blacklist database. when you even try to comment in another blog which has this plugin, it will avoid it
There is some problem in comment page ... according to me just change your theme .. or reinstall your theme
It is a well known issue for which numerous people have found numerous fixes. As others here state, it could be an incompatiblity with an old theme or it could be Akismet. Most fixes seem to be here: http://wordpress.org/support/topic/wp-comments-postphp-blank-page-broken-comment-ability
As said above, it's spam related, you should reinstall your theme for a fast solution. Let us know...