I don't know what happened actually. Yesterday, it was just working fine. I recalled what I did to put me in this difficult situation this morning.
Yesterday, I was just editing posts with PhpMyAdmin.
Well, anyway, I disabled all plugin and find out what is not working. It's the Plugin [[LINK href="http://wordpress.org/extend/plugins/custom-permalinks/"]]Custom Permalinks[[/LINK]].
<strong>My problem is that I have about hundred videos in youtube, and each video is given with Custom Permalink set. I want to keep the Custom Permalink Plugin and get rid with Redirect Loop Problems. </strong>
I now disable my Custom Permalink Plugin and everything work as it is. But this of course is not a good solution.
Please help. If you need whatever codes and details plugin lists, please let me know.