ISPmanager by default uses Afterlogic as a web-interface for email management. Official documentation
How do I know access details to administrative panel?
Username and password are specified while installing Afterlogic. If you do not know your username and password, you may find them in the file data/settings/settings.xml (default location path is /usr/local/mgr5/www/webmail-afterlogic/webmail/data/settings/settings.xml) (in some versions in adminpanel.xml).
By default ISPmanager installs Afterlogic into the directory /usr/local/mgr5/www/webmail-afterlogic/webmail/
Afterlogic uses Dovecot for authorization.
In case of the error The username or password you entered is incorrect. make sure that Dovecot is up and running.
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