The upgrade procedure or redis reset the ownership of the database to the default user "redis". For historical reasons, we are using the user "kluser" (because Kaspersky did not allow to use anything else). After upgrading redis, you must set the ownership to kluser on both /var/run/redis and /var/run/db On mail server: sudo chown -R kluser /var/run/redis sudo chown -R kluser /var/db/redis