A method of using a remote computing device to remotely diagnose a fault with a primary user device, the method comprising: receiving, at the remote computing device, a request from a secondary user device to diagnose a fault with the primary user device, wherein the request is received on a first communication channel, wherein the primary and secondary user devices (110, 116) are within a user environment and the remote computing device is located in a support centre which is not within the user environment; connecting, in response to the request, the remote computing device with the secondary user device using a secure communication channel which is different to the first communication channel; sending, from the remote computing device, a connection command to the secondary user device to connect to the primary user device using a third communication channel which is different to the secure communication channel and thereby allowing communication between the remote computing device and the primary user device via the secondary user device; sending a command message for the primary user device from the remote computing device to the secondary user device via the secure communication channel wherein the command message is selected from a command to initiate a diagnostic test and a command to change a configuration setting and is sent from the secondary user device to the primary user device using the third communication channel; and receiving, in the remote computing device, from the secondary user device via the secure communication channel, any response to the command message issued by the primary user device; whereby the response is used at least in part to diagnose the fault. receiving, at the remote computing device, a request from a secondary user device to diagnose a fault with the primary user device, wherein the request is received on a first communication channel, wherein the primary and secondary user devices (110, 116) are within a user environment and the remote computing device is located in a support centre which is not within the user environment; connecting, in response to the request, the remote computing device with the secondary user device using a secure communication channel which is different to the first communication channel; sending, from the remote computing device, a connection command to the secondary user device to connect to the primary user device using a third communication channel which is different to the secure communication channel and thereby allowing communication between the remote computing device and the primary user device via the secondary user device; sending a command message for the primary user device from the remote computing device to the secondary user device via the secure communication channel wherein the command message is selected from a command to initiate a diagnostic test and a command to change a configuration setting and is sent from the secondary user device to the primary user device using the third communication channel; and receiving, in the remote computing device, from the secondary user device via the secure communication channel, any response to the command message issued by the primary user device; whereby the response is used at least in part to diagnose the fault.