error screen appears when a person is not looged in

Hello, I need to find the reason why persons not logged are presented with an error screen. It is very confusing to the members of this site. For example the following link http://www.verenigingzonn.nl/wp-admin/admin.php?page=cpm_projects&tab=message&action=single&pid=1628&mid=1647

What is neccesary to make a redirect to the homepage?

Thank you for looking into this
regards
Geert

Hello,

I don't understand, you've provided an URL to your backend, so it's normal that users not logged in can't see this page, and see "YOU MUST LOG IN TO ACCESS THE ADMIN AREA." error page.

Generally user should see the backend login form, but I remember that you are using some login/redirect plugin.

I sent you PM

Yes Piotr, I do use a plugin to use a different login page, because in the feature settings of M Social it does not work properly by itself. So what needs to be changed in order to get a proper page for users not logged in instead of this confusing error page?
Help here is really appreciated.
regards
Geert

Sorry, but I still don't understand, so you want to allow not logged in users have access to your backend pages? Please check any other default theme with wordpress, when you are trying to access any backend page you have to log in (login form or error page is displayed), it's wordpress feature.

No they need to be shown a link where they can log in Piotr. Hope this is clear now
So what is possible to make this happen?
regards
Geert

Please deactivate your plugin and check again, if this problem is caused by the plugin, please contact with the plugin support/aouthor.