Permissions ISsue

This is probably a conflict with another plugin or theme. Disable all your plugins and use the default theme, then enable your plugins one at a time until you find the one causing the conflict.

Also, check in your discussion settings to make sure your comment settings are set properly.

I have the same problem and I’ve tried all of the above.

Try accessing the settings by going to Settings -> Rizzi Guestbook. Right now the link from the plugin page is broken which is why you are receiving that error. I am sorry about the inconvenience. I will be fixing it on the next update, which hopefully should be within a week. If you are still having issues, you can get to the settings page by entering this in the address bar of your browser. yourwebsite.com/wp-admin/options-general.php?page=rizzi-guestbook

I hope this was helpful.

Same here.
Ling in Plugin Site to settings does not work.

Target of the link url is /wp-admin/options-general.php?=wp-vipergb
Maybe it is helpful.

Thanks for fixing soon.

Tom