Error at roundcube logout

[Adrian]

Hello,

I have a problem at my server if in https://server/roundcube a logged in user make logout.

It comes a error message like:

----
REQUEST CHECK FAILED
Access to this service was denied due to failing security checks!
Please contact your server-administrator.
-----


Inside the panel I don't have some error messages.
Do someone know what's happen here and why?

Thank you, Adrian

[dragon]

I've the same problem with roundcube, however roundcube on debian 9 works well.
So, problem exist on debian 8, empty inbox, and I'm unable to send any email.
Thankfully afterlogic works well