Plesk backup is created with warning: Unable to back up website skeleton. Error: Failed to create archive: Transport error: File or dir 0 not exists

Symptoms

Plesk backup is created with warning:

Unable to back up website skeleton. Error: Failed to create archive: Transport error: File or dir 0 not exists

Cause

Virtual Host Template is corrupted.

Resolution

1. Connect to the server using SSH or RDP.

2. Restore the virtual host template:

   # plesk bin skeleton --reset admin