A password of the Plesk "admin" user is lost.
How to get/reset it?
Connect to a Plesk server via SSH and use the instructions applicable to your Plesk version.
Note: The commands presented below to change the admin user password, do also change the password for MySQL "admin" user. To restore the password for MySQL "admin" user, visit this KB article.
Plesk Obsidian / Plesk Onyx
Getting a password
For security reasons, the command to retrieve a Plesk "admin" password has been removed starting from Plesk Onyx.
Use a one-time login link to log in to Plesk without a password. To generate a one-time login link:
Run the following command to generate two links: One - to access Plesk by its hostname, another - by server IP address:
# plesk login
Note: If a server hostname is not resolvable from the Internet, hostname link will not be generated.
Copy one of the generated links and open it in a web-browser.
Plesk 12.x / Plesk 11.x / Plesk 10.x