I used the serial number and it says "Serial number does not exist"

[Clint Walker]

I am so frustrated that the only way to get help is truly remote.  I only have one activated computer and ready to set up Nitro on another one.  I used the serial number and it says it does not exist.  There has to be a better way to get an easy question answered than going through this process.

[Allain Umailin]

Hello @Clint Walker,

Thank you for reaching out to us through our Community Forums!

The error that you are receiving is commonly caused by installing a different version of Nitro PDF Pro. To fix this, kindly uninstall your current Nitro Pro through Control Panel\Programs\Programs and Features and reboot your machine.

To further assist you, I just adjusted your license, so please download Nitro PDF Pro 13 using these links:

x64   https://downloads.gonitro.com/professional_13.70.7.60/en/vlp/nitro_pro13_x64.msi 
x32   https://downloads.gonitro.com/professional_13.70.7.60/en/vlp/nitro_pro13_x86.msi

To know if you have a 32-bit or 64-bit Windows system, please refer to this article:
https://support.microsoft.com/en-ph/help/15056/windows-32-64-bit-faq

You can now activate your copy of Nitro PDF Pro by going to the Help tab > About Nitro Pro > Activate, entering your serial number 504907-xxyyzz097469, and clicking Activate.

Thank you for choosing Nitro and I hope this helps.