Useful telephone Information
Test your phone in the master socket before contacting your service provider!
Until recently British Telecom were responsible for providing and maintaining your phone line. However OFTEL have now allowed other companies to provide telephone services and therefore BT do not directly maintain any phone lines or equipment, even if you pay your bill to BT. This job is now the responsibility of Openreach. Openreach are the only company that can maintain your phone line up to the demarcation point in your premises.
What is a demarcation point? Normally it is a NTE5 or master socket like the one pictured below, however it could be any number of other connection points depending on how your phones have been wired in the past.