Hello There. I am Bing and I look forward to helping you with your issue today.
May I know the model, generation and version of your TimeCapsule?
Why do you want to connect it by ethernet if it is already connected to your network? It actually is your network...
If you are using the Time Capsule as your WIFI router you do not have to connect it directly to your computer, it is already on your network and can be accessed that way.
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