403 error page, configure Authorize.net payment method?

[surf1punk]

I cannot seem to choose Authorize.net as the payment method, as soon as I do and save the config, and go back in to set the config settings, any action results in a 403 forbidden page?

Is the Authorize.net plugin not working in the most recent version?? Is there a fix for this?

version
2.0.6

[vverloop]

Is the CHMOD on the directory's set right?