admin display/layout problem: blank area below menu

I cannot figure out how I got this blank white space in my admin panel (see attached) below the file menu and above the orders table.

Can someone point me to the relevant file?

Blank or partially blank page issues

Searched the tutorials for "blank Page"

https://www.zen-cart.com/tutorials/index.php?article=82

Kobra,

Thanks for searching on my behalf. Per the blank page (or blank part of a page) help doc I overwrote all the admin folder files. No change.

I uploaded a php file to turn on strict error reporting. No php errors displayed.

I've read this sentence 20 times and still don't quite understand it:
If you're dealing with blank admin pages, for the upload destination, substitute the /admin/includes/extra_configures folder instead of /includes/extra_configures where mentioned in the instructions.

Any other thoughts? Anyone?