wp-admin/edit.php?post_type=page shows blank page

Have you tried disabling your plugins?

Yes, I disabled all of them and still have the issue.

Have you tried changing your theme to the default 2012 WP theme?

Yes, the issue persists.

Go to your wp-config file, and change the WP_Debug constant to true. See if any message appears on that screen.

I have several

Notice: Undefined offset: 1 in /home1/xxx/public_html/wp-admin/includes/upgrade.php on line 1568

WordPress database error: [Multiple primary key defined]
ALTER TABLE qmi_bsk_pdf_manager_cats ADD PRIMARY KEY (id)

WordPress database error: [Multiple primary key defined]
ALTER TABLE qmi_bsk_pdf_manager_pdfs ADD PRIMARY KEY (id)

Notice: Undefined index: management_obj in /home1/xxx/public_html/wp-content/plugins/bsk-pdf-manager/inc/bsk-pdf-manager-category.php on line 23

Are you sure the bsk pdf manager plugin is disabled? Because that is what is triggering these errors.

bsk pdf manager plugin is disabled. No message on screen now, just blank

It seems like that plugin corrupted your wp installation. Does your theme have any custom post types that you could test if those edit screens are also corrupted?

Under posts, there are only 2 posts and I am able to edit them.

Not sure what you mean by custom post types.

What WP theme are you using?

DonateNow Theme Forest

I can add a new page. I can also go to the front end and view any page, click on the edit page in top wp menu and edit it.

My feeling is that when that plugin was updated or modified the database it ended up corrupting your installation. This original error Notice: Undefined offset: 1 in /home1/xxx/public_html/wp-admin/includes/upgrade.php on line 1568 is part of the function that allows authors to modify the database.

I would recommend reinstalling your wp install, but if someone else can take a look at this before you have to under go that pain.

Thank you! I appreciate all of your help.