Missing post editor toolbar and weird WP error

I just migrated my site to a new host, and since then, I’ve not been able to write or edit posts. Reason: The post editor toolbar is missing, and parts of the index page renders on the post being edited.

On another site, when attempting to add an image to a post, clicking on the image’s thumbnail redirects to the site’s index page.

The error logs shows this entry:

[error] [client IP] File does not exist: /home6/public_html/wp-admin/wp-content, referer: http://www.site.com/wp-admin/post.php?post=21984&action=edit

You can see that it’s looking for wp-content under wp-admin, which is weird, because WP is not set up in that manner.

Any clues?

TIA.