Roundcube Webmail fails to open!!!

[Curling Clermont]

Hi,
Try to acces my Roundcube Webmail from the control panel, as usual, but the new pop-up window waits for 1-2 minutes and stop at the login username and password screen. Cliqued on the Connexion button, but same result... Any clue???
Thank's

 

[zEitEr]

Hello,

Server is probably overloaded: PHP-FPM/MySQL or short on free resources: CPU, RAM