Login suddenly blocked and lost the formatting of view site

Hi

I have a German (https://www.visioform.com/wpde/) and English blog (https://www.visioform.com/resources/) that are identical, and without changing any file, the German blog lost its format and I can’t access the admin side. The English blog still works fine.

I get the following URL if I want to access admin

“https://www.visioform.com/wpde/wp-login.php/wp-content/plugins/mygallery/myfunctions/wp-admin/wp-admin/wp-admin/wp-admin/wp-admin/wp-admin/wp-admin/wp-admin/print.css”

My server tells me that the databank works okay. Does anybody have any idea which file might have been corrupted and what needs to be corrected?

I uploaded several ones

wpde/index.php
wpde/wp-config.php
wpde/wp-login.php
wpde/wp-layout.css
wpde/wp-admin/index.php
wpde/wp-admin/wp-admin.css

without success. I established wordpress in 2004/2005 and realise, I am not fit anymore. Can anybody help?

Thanks a lot
Ulla Sebastian