where can I buy an official replacement power lead for xbox one s?

Hi, I suggest you to buy a compatible one since this kind of cable are universal. Microsoft itself do not fabricate these cables (they purchase them from third parts) and they do not sell it on their official webstore... maybe you can find one of them
in a phisical Microsoft store (because these cables are used also for other elctronic devices), but as I suggested before you can buy an identical one where you want because they are universal.

I don't know if this will lead to the actual power cable, but you can try the following:

Go to
https://devicesupport.microsoft.com and sign in with your Microsoft Account.

If not already done so, register your console.

Click on the console and start a service request.

In the first drop down menu, choose that you have trouble with an accessory. Then select the power adapter (which usually means the external power adapter for the original Xbox One).

Follow the request through, and see if that results in a power cable sent to you.

If the replacement costs (too much) money, then cancel the process, and simply order any fitting cable that can sustain at least 200 Watts. Other than that requirement, it's a regular power cable, and nothing Xbox specific.

So there are options, but not directly from Microsoft. The Xbox One S and X have an internal power supply, so you can buy a replacement cord, but for the Original Xbox One they no longer service/replace/sell the power supply for that model.

This article has some information on the best place to buy a power supply for your Xbox One, but please make note of purchases and regions in terms of voltage and wattage.

You can buy a new power brick to use which was made for Xbox 360's in Germany.

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By an adapter do you mean a non-Xbox 360 power brick, if so it is not recommended to do so as you can damage your console by using un-official equipment, especially when powering it up.

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As for where to buy one I cannot help you there unfortunately.

So where do i get a replacement power supply?

I can find them on amazon or ebay for absolutely ridiculous prices (60€ and more) but the german Xbox homepage is surprisingly unhelpful. It´s supposed to have a link to all official retailers for replacement equip etc. but the link isn´t working ^^ so if
anybody could post a working link for all the official Xbox replacement gear retailers in germany than i would be very happy ;-)