Unexpected problem with my site; I happened to check it last night and noticed that the theme formatting and images have disappeared (the site's text is showing, but without any of the style sheet or theme formatting)... The site hasn't had any updates or modifications, so I assumed it must be a server problem. My host (JustHost) state that they do not provide support for 'this issue'.
In Dashboard > Appearance > Themes > Manage Themes the small preview images for the installed theme (Magazine-Basic) and the Twenty Eleven theme are missing (grey box/broken image icon). Similarly, the Magazine-Basic thumbnail image in Dashboard > WordPress Updates has a broken image icon.
I have the latest version of WordPress, and have tried re-installing. I have checked permissions (755) in my File Manager and double-checked with my FTP program. I've restarted. I've deactivated each plugin one at a time, deactivated all plugins together, and activated each in every sequence I can think of. I've willed it to work. I'm flummuxed, especially because two other sites - with identical versions of WordPress, theme and stylesheets are fine and dandy? The site is: strickdesignkurse.de and links to the two near identical sites are on the homepage.
Any help would be very gratefully received.