The backup file obtained from the Plesk Backup utility is a multi-part mime-encoded file. Each component within the file is for a specific purpose or location. There are individual areas for the configuration files, databases, SSL certificates, mail, and websites. The backup file is useful if you wish to restore an entire site or server. However if you need only a specific directory or a selection of files, the restore functionality with Plesk does not allow this. Instead you will need to follow the instructions below to separate the components and then extract the information you need.
The process is to use a program like ripMime (project page: http://freshmeat.net/projects/ripmime/) to extract out the different mime-encoded components of the backup file.
To download this program into the current directory (I would suggest doing this in /root) use the command
and then extract it with the command
tar -zxvf ripmime-188.8.131.52.tar.gz
Once the program is downloaded and installed, you can then run the command
/path_to_file/ripmime /path_to/backup_file /directory_for_extracted_filesto extract the individual mime-encoded components into the directory you specified.
Once the files are extracted, you'll be able to use the 'tar' command to extract all or only specific files from the backup files present. You'll need to identify which file contains the information you are looking for, so you will need to run the command
tar -ztvf /directory_for_extracted_files | grep directory_or_filename
Once you know which file contains the information you are searching for, you can then extract the directory or file with the command
tar -zxvpf /directory_for_extracted_files/filename_containing_information directory_or_filename
Once the directory or file is extracted, you can then move it to the proper location. The permissions and file ownership should be correct as long as you use the 'mv' command since we preserved ownership and permissions with the 'p' flag in the 'tar' command.