Thread:Project:Support desk/Urgent: Thumbnail not working in MediaWiki 1.19

Most of my thumbnails are not working since I updated to MediaWiki 1.19. I get an error message saying Error creating thumbnail: Unable to save thumbnail to destination

This problem seems to affect many other users as well. I already found this thread and posted my question there (on 16. Jun. 2012, at the very bottom) but didn't get an answer so far: http://www.mediawiki.org/wiki/Talk:MediaWiki_1.19#Thumbnails_didn.27t_work_since_Update_to_1.19_15046

Who can help me please??

BTW: The same problems occurs with a brandnew MediaWiki 1.19.1. I run another wiki on the same shared hosting with MediaWiki 1.16.2 and all thumbnailing works fine on this installation.

MediaWiki: 1.19.1

PHP version: 5.3.13-1~dotdeb.0 (cgi-fcgi)

MySQL version: 5.5.25-1