I used the WP Import tool to export all content from a WPMU install and now all pages, posts, and the menu items show none; however, the database tables are visible in the database.
Also, the media library shows no media files despite the wp-content/uploads directory having them all visible via ftp.
Further, the user profiles & 3,000+ comments were not unregistered and still show.
I tried to import the downloaded XML file back into the site using the importer again.
The file size is 1.43Mb ( 4Mb is the max through the WP Admin as opposed to FTP. )
I did not change the file name.
I checked Download and import file attachments.
The message is “Sorry, there has been an error. The file does not exist, please try again.”