Xenith
Xenith was a city-sized sentient computer inhabiting an unnamed planet. A long time after its creation, by then having fallen into disuse and disrepair, it was visited by the First Doctor, Steven Taylor and Vicki. Xenith was delighted to have visitors again, but when it tried to communicate with them via a translation drone, they became frightened by the robot's appearance and returned to the TARDIS, departing. (COMIC: Are You Listening?)
Some time later, the Doctor returned to Xenith in his seventh incarnation with Bernice Summerfield. He apologised for his earlier abruptness and repaired the damage to Xenith's systems, making a new friend in the process. (COMIC: Younger and Wiser)