Hello, I am having some issues with Ispconfig3 cluster and Roundcube giving errors such as "Your session is invalid or expired." after short periods of time, or even randomly. OS is Debian 8. Ispconfig3 is up to date on master + slave. Using memcache as backend with roundcube (using DB does the same thing). /var/log/roundcube/errors is empty /var/log/apache2/error.log does not appear to show anything relevant. Code: [Wed Dec 27 11:21:25.613565 2017] [:error] [pid 1159] python_init: Python version mismatch, expected '2.7.5+', found '2.7.9'. [Wed Dec 27 11:21:25.616688 2017] [:error] [pid 1159] python_init: Python executable found '/usr/bin/python'. [Wed Dec 27 11:21:25.616715 2017] [:error] [pid 1159] python_init: Python path being used '/usr/lib/python2.7/:/usr/lib/python2.7/plat-x86_64-linux-gnu:/usr/lib/python2.7/lib-tk:/usr/lib/python2.7/lib-old:/usr/lib/python2.7/lib-dynload'. [Wed Dec 27 11:21:25.616769 2017] [:notice] [pid 1159] mod_python: Creating 8 session mutexes based on 150 max processes and 0 max threads. [Wed Dec 27 11:21:25.616781 2017] [:notice] [pid 1159] mod_python: using mutex_directory /tmp [Wed Dec 27 11:21:25.831977 2017] [ssl:warn] [pid 1159] AH01909: SERVER2HOSTNAMEFQDN:8080:0 server certificate does NOT include an ID which matches the server name [Wed Dec 27 11:21:25.832395 2017] [ssl:warn] [pid 1159] AH01916: Init: (DOMAINNAME:443) You configured HTTP(80) on the standard HTTPS(443) port! [Wed Dec 27 11:21:26.189754 2017] [mpm_prefork:notice] [pid 1159] AH00163: Apache/2.4.10 (Debian) mod_fastcgi/mod_fastcgi-SNAP-0910052141 mod_fcgid/2.3.9 Phusion_Passenger/4.0.53 mod_python/3.3.1 Python/2.7.9 OpenSSL/1.0.1t configured -- resuming normal operations [Wed Dec 27 11:21:26.189940 2017] [core:notice] [pid 1159] AH00094: Command line: '/usr/sbin/apache2' Using DNS round robin for both servers, with HTTPS to access roundcube. Server1 + Server2 use the same cert, which has the domain name as SAN. Roundcube is accessed via https://domainname/webmail I think this has only been happening for a couple of months. Can't think of any changes that would have caused this. Similar issue here with no replies; https://www.howtoforge.com/community/threads/your-session-is-invalid-or-expired.77772/ Does anyone have any idea or may be able to point me in the right direction? Thanks.