If you have your own local mail server you may encounter problems sending emails through some spam filtering systems because of security processes known as reverse DNS lookup (rDNS).
If you have set up custom reverse DNS with BT but wish to change or remove it please use our Reverse DNS form .
You'll need to include the following information when you fill in the form:
- Broadband number - If you aren't sure what your number is, plug a telephone into the socket and dial a mobile number which should then display your broadband number (if it's withheld then dial 1470 before the mobile number).
- Broadband Account number - This is the account that your static IP number is on.
Fully Qualified domain name. - These could be displayed as
Non fully qualified domain names could be displayed as www.example.com or example.local.
- IP Address that you want to change/remove.
We will reset your rDNS to the default settings unless you provide any special instructions.
Requests are processed manually and are usually completed within two working days, however, delays may occur during periods of heavy demand.
A confirmation email will be sent once the form has been received. When the changes have been processed a further email will be sent to confirm the changes to your rDNS.