In principle, the respective licensing terms of the manufacturer apply. For Microsoft products, a product key is generally intended for activation on one device.
This means that a separate license is required for each additional computer. The simultaneous use of a single product key on multiple devices is not permitted in most cases and may violate the manufacturer's licensing terms.
Exceptions
Some products are explicitly offered as multi-user or multi-device licenses. In these cases, the number of permitted installations is specified directly in the product description.
Please always refer to the respective licensing information of the purchased product.
If you are unsure how many devices your license is valid for, our support team will be happy to assist you.