# Authenticate from IMAP The interfacing of GLPI with mail servers as a source of authentication. This authentication source is configured from the menu `Setup > Authentication > Mail servers`. This ability can compensate for the absence of directory or of CAS server. However, contrary to what is possible with other sources of other authentication sources, no mass import is available. A user is authenticated by GLPI if the server of mail server has authenticated him beforehand. The connection to the mail server uses the IMAP or POP protocols. The options of SSL and TLS encryption are available. The distinction is made between the mail domain which is the part of the of the mail address that follows the asterisk character, and the fully qualified name of the mail server, which can serve several mail domains. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://help.glpi-project.org/documentation/modules/configuration/authentication/imap.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.