Cannot share a file by emailing a link

I have a zip file in a public folder on my WD My Cloud Mirror Gen 2 that I want to share with someone by sending a link to that file. So I right-click on the file in the WD My Cloud app and choose Email in the drop down.
The email gets sent OK, but when the recipient clicks on the link to the file, they get an error, “401401 Request is not allowed”, and they are unable to download the file. Can anyone tell me why this procedure does not work and how I can send a link to the file that will work?

Thanks.

Hi there, have the recipient copy paste the link received and to open it on a different browser.

We have tried it with Safari, Firefox, and Edge and it fails on all three, with several different files.