: Older versions of Nitro Pro use obsolete security protocols. The activation servers will reject connections from these outdated builds.
If you encounter issues with your Nitro Pro activation certificate, here are some common troubleshooting steps: nitro pro activation certificate
If you are using an early build of Nitro Pro 13 or 14, you may be hitting a known bug where the software cannot process the updated server certificates. : Older versions of Nitro Pro use obsolete