Blank Screen after Logging In as Admin

I just logged into our admin panel to post a blog, and once logged in, I can see the menu appearing on the left hand side, but the main section of the screen is blank/white. I can click on posts, pages, widgets, etc. but nothing appears.

I’ve followed the instructions to rename the PlugIns and Themes in order to deactivate them, but the blank screen still shows.

Does anyone know what we can do to rectify this?