I have done what you suggested but it´s still not working.
Thats my .htaccess
# If you are having problems with the rewrite rules, remove the "#" from the
# line that begins "RewriteBase" below. You will also have to change the path
# of the rewrite to reflect the path to your XenForo installation.
I tried to take out the addons and also reverted all templates, had also some outdated after upgrading to rc2, but i still cant get it working. Last time i was uploading images was at Beta6 and there was everything fine.. So i have NO clue. This are just weird "errors"
Well i send Mike all Details. Hope he will find some time to take a look to it.
I just checked my Server Error Logs and this is what i get when i try to upload an image
move_uploaded_file(/var/www/vhosts/brainlag.eu/httpdocs/internal_data/attachments/0/67-7a8e602f280733ef8bdedec83ac0541d.data) [<a href='function.move-uploaded-file'>function.move-uploaded-file</a>]: failed to open stream: Permission denied