: Firewall restrictions, proxy servers, or lack of internet access.

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If you cannot find your activation certificate, you can locate your serial number via: The confirmation email sent at the time of purchase. The Nitro Account Portal. 2. Upgrading Versions

On first launch after activation, Nitro Pro writes the certificate to:

: Ensure your firewall allows outbound connections to https://gonitro.com . If you are behind a corporate proxy, white-list this URL or speak with your IT department about offline certificate generation.

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A: The number of activations allowed depends on the End User License Agreement (EULA) of your specific license. Typically, a standard single-user license is intended for use on one primary computer, but it may allow for activation on a second device like a laptop, as long as both are not used concurrently.

Save your original purchase invoice and license certificate email in a secure location.