[Plugin: Google Analytics for WordPress] "Update Google Analytics Settings" gives error 50

When trying to save the settings, im getting a ‘internal HTTP error, 500’, the web page can not be displayed ect.

There is not change whatever i type in the UA code by hand or try to authenticate with Google.
It gives the samme error when hitting : “Update Google Analytics Settings”

Thanks

http://wordpress.org/extend/plugins/google-analytics-for-wordpress/