Thread:Project:Support desk/MW 1.23.3 - "404 Not Found" then I try open uploaded images or generate thumbnails

Recently I installed Wiki on hosting.

MW 1.23.3

PHP 5.4.4-14 + deb7u12 (apache2handler)

MySQL 5.5.38-0 + wheezy1-log

When downloading images I discovered the problem – thumbnails do not generate and I can’t open images. When you try to open Wiki shows error "404 Not Found". I suspect that I have a problem with access to the temp folder for uploaded images, as I had a similar problem on older versions of MW. How I can fix this problem and what a bug is it?