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Open the custo service center and login as the Supervisor (default Password is "custo") and go to License (1) Menu. Click on "Install new license online" (2).
In the next Dialogue enter the License Holder Name (Normally the Customer who is using custo diagnostic) and the License UID and press OK (the License UID can be copy from the Software Confirmation Document - if you get it as an PDF File) an example is shown below.
You can also watch the INSTRUCTION VIDEO.
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