How to fix admin stylesheet muck-up?

I have no idea what’s going on here.. running the latest version, just logged in and I find my admin area looking like this:

enter image description here

To me it looks like it’s missing some/many styles and in load-styles.php in the inspector it’s showing a bunch of gibberish and I have a ‘Uncaught SyntaxError: Unexpected token ILLEGAL’ error twice on loadscripts.php. I tried reinstalling the current version of WP and nothing changed. Then I reuploaded the load-styles.php (same size) from the base wordpress files, and it started working.

Then suddenly it was doing the same thing on another of my sites. I tried the same trick (and also with load-scripts.php (this time though the load-styles was much larger so I backed it up) but that didn’t help.

The only thing I can imagine might be causing this is the iOs wordpress app because I recently added it to both blogs. That’s the only change I’ve made in the last little while and I’ve been on the sites before with no issue.

Solutions Collecting From Web of "How to fix admin stylesheet muck-up?"

I had the same issue just a moment ago on a local MAMP install of WP, added the following line to my wp-config.php and it fixed it for me:

define('CONCATENATE_SCRIPTS', false );

My screen looked exactly the same yesterday while I was developing a widget. The problem for me was an an unclosed div tav. You might try inspecting elements on the page. In chrome or safari you can right click and select ‘Inspect Element’ and see what’s going on.

Well, this may not identify the precise issue, but why not just make a backup of your site, as-is, and re-run the most recent WordPress update?