To access your mailbox through webmail, do any of the following:
In a Web browser, visit the URL webmail.yourdomain.com, where yourdomain.com is the Internet address of your website. When prompted, specify your full email address as the username (for example, yourname@yourdomain.com), and specify the email address password.
When logged in to Plesk, go to E-mail-addresses, and in the list of email addresses, click the webmail icon corresponding to the email address you need.
Note: If you cannot open the webmail page, make sure that a webmail solution is enabled. Open the Mail section, then the Mail Settings tab, click the name of the domain for which webmail is inaccessible, and select a webmail client in the Webmail menu.