I'm getting The request was aborted: Could not create SSL/TLS secure channel error on check out with FedEx plugin. Version 4.0. It's happening in prod only and fine in test and dev. Any suggestions how to fix it. Thank you so much Len
Recently I had two clients using UPS that were getting that same error. What worked for them was to use IISCrypto and click the “best practices” button and then restart the server.
Did you disable the protocols TLS 1.0 and TLS 1.1 via the IISCrypto GUI? Did you reboot the server? (Then I recommend again run IISCrypto and check to be sure TLS 1.0 and TLS 1.1 are not still enabled.)