Site diplay feeds once in a while

I know someone around here can help me with our problem.

It all started when our site throws an Error 404 when we login. I searched some related issues and found out that we just have to change file permissions of all directories (wp-admin,wp-content,wp-includes) to 755. It was indeed the solution but after a few days, it starts displaying latest content feed instead of the link (pages,posts,tags,categories,archives) you clicked.

I would resort to re-installing the site if ever the problem persist but its better to raise the issue here first.

btw, here’s our site Cotabato Exchange Daily