Elementary. System backups are deleted to prevent registry conflicts with old files which will be restored with restoring old Windows files and registry, coz RP3.5+ files are highly uncompatible with other system files. I'm agreed that this is unintellegent command to workaround several backup/restore errors, but i WON'T fix it in RP4. - RP is ended. - Better use RP3.6. - It warns that product is dangerous and backup/restore is not reliable. Backup is NOT by default. - This issue is not present in RPLite.