Error Sending Data (12029)

I have a client that tried to activate my product on Windows 7 with Excel 2013 32-bit and they get this error when they enter the activation code and press “Activate.” They don’t appear to have any firewalls or issues on their end; they’ve tried it on two different internet networks. My site is using HTTPS.

For reference, I am able to successfully activate products on other PC’s with various versions. Any ideas of what I could try to resolve this? I’m truly at a loss.

Thanks!

The complete message was:
“Error sending data: (12029) A connection with the server could not be established.”

This means that the secure connection could not be made. Maybe your server is only accepting TLS 1.2 and your customer on Windows 7 has not an updated Windows copy. They should try this:
https://support.cybersource.com/s/article/How-do-I-enable-TLS-1-2-on-Windows-7