Do the following if you ever face any issue like “Session Invalid or Expired” when logging into RoundCube.
1. Log in to the server.
2. Access the following file.
3. Comment the line.
$rcmail_config['session_lifetime'] = 10;
( It is not recommended because session timeout is a security feature. You can also try to increase the default value – 10 to a higher value. )
4. Save the file.
That’s it!! That’s how you fix Session Invalid or Expired RoundCube issue.