I finally figured out how to do this relatively easily. On my dashboard, I chose “posts” and then in the upper right selected “screen options.” Under the “Show on screen” choice, I upped the number of posts to show on screen at a time. Since I have more than 2200, I tried 3000, but that gave me errors, so I set it to 500 and clicked apply.
First I selected only my “published” posts. Then I was able to tick the box next to “title” under “bulk action” (to select my first page of 500 posts) and drop down the menu to choose “edit” and “apply” After a pause, you should see some options to edit. For “pings” on the far right, I selected “allow” from the dropdown and clicked “update.”
Then go to the next page of posts and repeat the steps in the second paragraph. Repeat for as many pages of posts as necessary.
If you get a message that says, “Request-URI Too Large. The requested URL’s length exceeds the capacity limit for this server,” then you need to start over, setting your screen options to a lower number of posts displayed per page.
