No Signatures Found

Hi. I am new to GPG4Win and believe I almost have it all installed but for one issue…

When copying encrypted text to the clipboard, then choosing Clipboard->Decrypt, it reports:
Clipboard: No Signatures Found

But I have imported by public key.

I generated the public and secret key on a CentOS server. I then download the public key, and imported into Kleopatra. I then have a PHP script to encrypt some text and email it. I copy the email encrypted text, and then using Clipboard->Decrypt I get the error.

Does anyone know what I am doing wrong please?

Thanks