Websites hosted on a Plesk server hang on loading or show an error:
CONFIG_TEXT: You do not have permission to view this directory or page.
Attempt to view website files in Plesk in Domains > example.com > File Manager fails:
PLESK_ERROR: Error: Unable to display the file /var/www/vhosts/example.com/httpdocs/index.html.locked: Unsupported file format.
Website files have the extension
.lockedfiles include information about extorting money, for example:
The server was hacked and websites' files were encrypted.
Follow the instructions from the article What to do if Plesk server was hacked?