Hi there!
What the exact error message you’re getting? (Screenshots would help, too.)
Parse error: syntax error, unexpected ‘[‘ in /hermes/walnaweb09a/b1344/moo.chris23/wp/wp-content/plugins/wordpress-popular-posts/admin/class-wordpress-popular-posts-admin.php on line 858
Ah, it’s the same as this one. Do you know by any chance what PHP version you’re running there?
In any case, please follow the instructions I posted on the link above. It should fix the problem.
Sorry, just noticed you literally can’t log in into the dashboard. Please follow these instructions to disable WPP, then install it (but don’t enable it!) and follow the instructions from the link above.
An update that fixes this and other issues has been pushed to the repo. Please update as soon as possible.