not allowed into admin site

I tried to update wordpress and its plugins, and after the maintenance ran the website is a blank page and so is the admin login URL. I’ve tried on three different browsers. I contacted the host server and they said

“Executive Summary:

A WordPress plugin (all-in-one-seo-pack) you installed requires the
existence of several files or will refuse to run. At least one of those
files (opengraph.php) does not appear to exist in the location specified. I
do find that file in a separate sub-directory

wp-content/upgrade/all-in-one-seo-pack.2.4.2-x5khza/all-in-one-seo-pack/publ
ic/opengraph.php

So my guess is your web person uploaded some content in a non-standard
directory and the site can’t find it.

PHP Fatal error: require_once(): Failed opening required
‘/var/home/obelusdg/public_html/wp-content/plugins/all-in-one-seo-pack/publi
c/opengraph.php’
in
/var/home/obelusdg/public_html/wp-content/plugins/all-in-one-seo-pack/all_in
_one_seo_pack.php
on line 391”

But I don’t understand why that would disable the admin access page, preventing even login, and how just running the automated updates would place files in an inoperative location.

The page I need help with: [log in to see the link]