Permalinks give 404 with /%postname%/

Hello,

I am having a problem with the custom permalink /%postname%/ since it makes my pages blank with a 404 not found. This is one of the problems the second one it seems that it switches automatically to post name option even if i have a /%postname%/ custom permalink. For security i use bulletproof security plug in for the .htaacess files. I deleted the plug in and pasted some default code from one of the forum posts but that didn’t worked either. Also i am using the latest wordpress ver. 3.6. Any suggestions?