CobianSoft

That option is uncheck. I monitored the logs and I realized that the error does not occur with every backup but it is random, though frequent.

Hi, I've the same problem, my ftp server is on a Qnap NAS with ssl auth. Copy go perfectly, but old backups are not deleted. here some error from logs " ERR 2022-01-26 20:51:08 Impossibile completare l'eliminazione dei file su un server remoto: SSL/TLS required on the control channel (code=550) ERR ...