WordPress Admin Css not loading properly

Hello,

I’m a user that have worked with WordPress 2-4 years now. I’ve done some advanced stuff so I’m pretty good at this.

But now suddenly I’ve got problems with all of my WordPress installations that share the same web host. Some css is not loading for the admin pages, for example the WordPress logo on the wp-admin login page is gone. When I login, the buttons for example “publish” etc (that usually is blue) has no styling. This has came from nowhere and without any editing. I’ve tried to change theme and update to newest WordPress on different installations and even replace files without success.

Do anyone have a suggestion?

Thanks!