p01acos

But if you already changed the permanentlinks, you will have to do it to every single post.

I found a solution, for my case at least
It was the pernamentlink problem. When I created a new post with a title with some special characters like Apple‘s or Day‘s, server could not find the post because of this sign. Solutions is to keep your pernamentlink settings as you want, delete permanently (before copy it to a word or notepad) and create a new post, with title without any special characters. Please comment if worked.

Thanks for that. It was some plugin. But strange thing I desactivated them all, and after activated them all, and everything work how it should. Strange. Thanks SOLVED

Also when uploading an image for the post it also opens in the same window. Now I lost my whole work.

i found the problem. It was in settings of my theme. Anyway, now I want to keep this plugin Advanced Excerpt because it shows page image, but also a excerpt, but in post it shows it again. How to delete it. Do i have to play with the code, if so where and what to edit?
Thanks

i havent changed any code. i just installed plugin called Advanced Excerpt