Error during the restoration of backup: Repository error: File has wrong format

Applicable to:

The restoration of backup fails with following error:

PLESK_ERROR: WARNING: Restore domain "example.com"
Repository error: File has wrong format
The following error message appears in the deployer.log file (e.g. /var/log/plesk/PMM/restore-2018-05-15-21-20-17-106/deployer.log):

CONFIG_TEXT: INFO: RepositoryError[9ab88a1f-13dd-4859-87f9-3f765d79df8b]: Repository error: File has wrong format [common/plesk-utils/PMM/repository-transport/repository_utils.cpp:310]

Product issue:

#PPPM-6351 "Plesk no longer creates backups with the warning if they contained empty archives and the “Do not compress backup files” option is selected in the server backup settings."
Fixed in:
- Plesk Obsidian (RC1 18.0.15 as #PPP-29832) 04 June 2019 (Linux)

Please consider updating your server:

If update is not possible for some reason you may try the following

temporary solution

Until the bug is fixed, apply the workaround (for Plesk 17.5 and CentOS 7 only):

Note: The patched files can be overwritten by Plesk updates.

Connect to the Plesk server via SSH.
Create a backup of the files /usr/local/psa/admin/sbin/deployer and /usr/local/psa/admin/sbin/pmm-ras:

# cp /usr/local/psa/admin/sbin/deployer{,.orig}
# cp /usr/local/psa/admin/sbin/pmm-ras{,.orig}
Download the patched files and unpack them:
- for Plesk Onyx 17.5
  
  # wget https://support.plesk.com/hc/en-us/article_attachments/115000490773/deployer.tar.gz
  # wget https://support.plesk.com/hc/en-us/article_attachments/115000490793/pmm-ras.tar.gz
  # tar -xzf deployer.tar.gz
  # tar -xzf pmm-ras.tar.gz
- for Plesk Onyx 17.8
  
  # wget https://support.plesk.com/hc/en-us/article_attachments/360006175553/customfix_plesk178_PPPM-6351.zip
  # unzip customfix_plesk178_PPPM-6351.zip
  # cd ./customfix
Set the necessary permissions on these files:

# chmod 750 deployer
# chmod 750 pmm-ras
Place patched files instead of original ones:

# mv deployer /usr/local/psa/admin/sbin/deployer
# mv pmm-ras /usr/local/psa/admin/sbin/pmm-ras
Check that no errors are reported by newly copied utilities:

# /usr/local/psa/admin/sbin/deployer --help
# /usr/local/psa/admin/sbin/pmm-ras --help