This article defines various ways to get back into your Plesk Control Panel should you forget your administrative credentials.
Forgotten credentials for various version of Plesk.
Resolution
Depending on the version of Plesk, any of the following should work:
Plesk Onyx:
#plesk bin admin --set-admin-password -passwd new_password
use this to create a new administrative password.
#plesk login
use this to generate a temporary login.
Plesk versions 10.x-12.x:
# /usr/local/psa/bin/init_conf -u -passwd new_password
use this to create a new administrative password.
# /usr/local/psa/bin/admin --show-password
use this to show the current administrative credentials.
Plesk versions up to 9.x:
# cat /etc/psa/.psa.shadow
use this to show the current administrative credentials.