While configuring email account on BlackBerry, the connection could not be successful sometimes even though all the settings are correct. Sometimes, the mails even drops in spam or blocked as spam by the spam filter.
To avoid such problem, the BlackBerry mail server IP range should be whitelisted in the Iptables, CSF and Spam filter on the server.
| IP Address | Netmask |
| 206.51.26.0 / 24 | 255.255.255.0 |
| 193.109.81.0 / 24 | 255.255.255.0 |
| 204.187.87.0 / 24 | 255.255.255.0 |
| 216.9.240.0 / 20 | 255.255.240.0 |
| 93.186.16.0 / 20 | 255.255.240.0 |
| 68.171.224.0 / 19 | 255.255.224.0 |
| 206.53.144.0 / 20 | 255.255.240.0 |
| 67.223.64.0 / 19 | 255.255.224.0 |
| 74.82.64.0 / 19 | 255.255.224.0 |
| 173.247.32.0 / 19 | 255.255.224.0 |
| 178.239.80.0 / 20 | 255.255.240.0 |
| 5.100.168.0 / 21 | 255.255.248.0 |
|
131.117.168.0 / 21
|
255.255.248.0 |