This area of the forum is meant for community members supporting themselves.
I suggest you look at your website using firefox error console - you will see you have errors on the CB registration page - most likely because of something else on your website or even your template.
Thanks. It has worked for years and i don't know what the errors mean because i'm not a webdesigner myself.I now turned of the ajax check for the email and username so that it works. But if you could give me a hint what i could be i would love that. I know i work with a old version of joomla but that is because i use joomleague and cant update yet.