DLO 7.5 and 7.5 SP1 not sending stmp alert notifications by email

After install DLO 7.5 and now 7.5 SP1, i'm not getting smtp alert notifications by email. The DLO register all information but i'm not receiving them in my email. In 7.0 version, this feature works fine.
The only alerts i'm getting is "No backups in 14, 28, 7 days". All the other warning alerts (include erros and information) i'm not getting. 

For example the DLO generate the alert "No matching automated user assignment". DLO register this information in alerts tab console, but i'm not receiving in my email. Other alerts like backup sucessfull or no backups in 14, 28, 7 days i'm receiving.

Any idea?

Thank you!