I have noticed that there are times in WordPress where one particular page will not load, especially the “new post” page. This can sometimes be fixed by simply deleting your cache within WordPress. Always try to refresh your browser page first, but if that doesn’t work, sometimes we need to take it to the next level.
Every time you access a page, your browser will store a copy of the items needed to display that page to you. This is usually a good thing becuase it means that the pages you browse more commonly will load faster the next time you visit. Where this can be a problem is if the page is not loading properly because the cache is storing older supporting files and the page can no longer run.
Right within WordPress, there is a new Delete Cache feature located on the toolbar at the top of any WordPress window.
If you find you are stuck or a page is not loading correctly, this could just do the trick.