If you have your own office, try to ensure that the overall fung shui of your workspace works to your benefit. Stand at the entrance of the office and observe what lies opposite. It should preferably be a wall, not the fire extinguisher or axe. It should also not be at the end of a long passageway, as this will expose you to sha chi or attacking energy.
Working in an office with such a vulnerable entrance will ensure that you face numerous obstacles at work. You will have to relocate the entrance. Placing a Ba Gua mirror or a normal mirror will not reflect 'attacking energy'.
It may send negative energy back to your colleagues, as Ba Gua mirrors can only be used externally.
If you sit with your back to the door and face a great view, not only will you be constantly distracted, you may also be backstabbed by colleagues.
Reorient your desk so that you have a wall behind you and that you are able to see who enters your office at all times. Ideally, the views should be to your side, so that you can look up from your work occasionally to recharge yourself.
You should not have any windows directly behind you. Not only will there be a reflection on your computer screen from the glare, you are also vulnerable from a fung shui perspective as there is no support behind you. If your desk is fixed, consider simulating a wall by drawing the blinds, or placing a screen or billboard behind you.