| Software | Servidores | Porcentage |
|---|---|---|
| Postfix | 91 | 36.84 % |
| Sendmail | 54 | 21.86 % |
| QMail | 33 | 13.36 % |
| Exim | 16 | 6.48 % |
| Google Mail SMTP | 15 | 6.07 % |
| Microsoft ESMTP MAIL Service | 11 | 4.45 % |
| MDaemon | 6 | 2.43 % |
| eTrust Secure Content Manager | 6 | 2.43 % |
| PMDF | 5 | 2.02 % |
| eSafe | 3 | 1.21 % |
| ArGoSoft Mail Server | 2 | 0.81 % |
| InterMail | 1 | 0.40 % |
| Sun ONE Messaging Server | 1 | 0.40 % |
| IMail | 1 | 0.40 % |
| Lotus Domino | 1 | 0.40 % |
| MailSite | 1 | 0.40 % |