I disactivate all the plugin of my web site and I found that Nextgen public uploader is the plugin that cause the 500 error when I activate the Photo contest plugin
Hi Mario,
thank you for this note. It’s a general problem of NextGEN Uploader. You can’t activate any other plugin because NextGEN Uploader calls a class which not exists. It seems also that the plugin is out of life time:
https://ww.wp.xz.cn/support/plugin/nextgen-public-uploader
