The following is our apache config for the site: Alias /wiki /var/www/v-species/w/index.php Alias /openmedia /var/www/v-species/o/index.php <IfModule mod_rewrite.c> RewriteEngine on RewriteLogLevel 0 # permanent redirect "www.xxx.net/wiki/" to "xxx.net/wiki/" ALL OLD URLs RewriteCond %{HTTP_HOST} !^species-id\.net [NC] RewriteCond %{HTTP_HOST} !^$ RewriteRule ^/?(.*) http://species-id.net/$1 [L,R=301,NE] # redirect wrong uppercase: RewriteRule ^(.*)(/WIKI/)(.*)$ $1/wiki/$3 [R] # Thumb generation (see Manual:Thumb.php) RewriteCond %{DOCUMENT_ROOT}%{REQUEST_FILENAME} !-f RewriteCond %{DOCUMENT_ROOT}%{REQUEST_FILENAME} !-d RewriteRule ^/w/media/thumb/[0-9a-f]/[0-9a-f][0-9a-f]/([^/]+)/([0-9]+)px-.*$ /w/thumb.php?f=$1&width=$2 [L,QSA] RewriteCond %{DOCUMENT_ROOT}%{REQUEST_FILENAME} !-f RewriteCond %{DOCUMENT_ROOT}%{REQUEST_FILENAME} !-d RewriteRule ^/o/media/thumb/[0-9a-f]/[0-9a-f][0-9a-f]/([^/]+)/([0-9]+)px-.*$ /o/thumb.php?f=$1&width=$2 [L,QSA] I very much appreciate it if you can see what needs to be changed so that "&" and "+" are working. We have analyzed it and searched for people having similar problems. Both work fine for uploading and full size image, but thumb generation fails. We use a standard imagemagick thumb generator, nothing special as far as I know. Thumb generation from command line works fine, which is why we suspect the apache rewrites to be involved. Gregor