What causes would you consider if a user contacted you stating that they can't see the display on their system?

It is very common during an interview for a technical support engineer's position to be provided with specific scenarios or problems you're likely to encounter and asked how you would go about solving these. While there is no way to prepare for every single scenario you may be presented, you should have a general knowledge of the types of problems you will encounter in this role and how you go about resolving them. In the case that you do not know, the best response is to acknowledge this and then describe how you would go about researching the information needed to solve the issue.