To disable multiple identities in Roundcube you need to edit the following file: config/main.inc.php
and in it locate this section:
// Set identities access level:
// 0 - many identities with possibility to edit all params
// 1 - many identities with possibility to edit all params but not email address
// 2 - one identity with possibility to edit all params
// 3 - one identity with possibility to edit all params but not email address
$rcmail_config['identities_level'] = 3;
Setting the value of identities_level to 3 disables users to change the from email address.

![WARNING: [pool user_USERNAME] server reached pm.max_children setting (25), consider raising it Screen Shot 2020 06 23 at 09.57.51 - WARNING: [pool user_USERNAME] server reached pm.max_children setting (25), consider raising it](https://i0.wp.com/administrator.pejcic.rs/wp-content/uploads/2026/09/Screen-Shot-2020-06-23-at-09.57.51.png?resize=344%2C194&ssl=1)

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