The procedure depends on the type of cable, the age of the cable, and its history. -> Write a letter, and wait.
General "problems" such as "my computer crashed" are not related to spare parts; in such cases, the following services can be offered:
http://shop.dieselschrauber.de/diagnose-livesupport-systemsupport-p-78.php
From time to time, we receive anxious inquiries from customers who use our systems for commercial purposes and whose entire business operations depend on them.
Given the affordable price of our systems, it makes sense to purchase a backup system (with a 10% discount on the second purchase), which would then be immediately available.