When I tried using it with a shared link,When I try to download a file, a pop-up like the one below appears.
People can download without signing up or logging in.If this is displayed when sending to an external business partnerSome of you may be worried, "Do I need an account to download?"Please tell me how to eliminate this display.
Hi 
Welcome to the Box Community! I certainly understand your concern regarding this the login/sign up message.
At this time, there is not a way to disable this pop-up message for users. This is the expected behavior if users are downloading from a shared link without being signed in to Box. If a user is signed in to Box, then navigates to the link, the pop-up message will not appear for them.
With this said, shared links do not require users to have a Box account. However, they will continue to receive the pop-up for any download attempt if a Box account is not being detected.
I understand the concern regarding sending shared links to external partners, and we will definitely take this feedback into consideration. Our Product team is constantly looking for ways to improve Box based on user feedback, so I recommend for you to upvote this idea in Box Pulse or post other feedback/idea to help us shape the future of Box.
I hope this clarifies your concern and thank you for your understanding. Have a great day! 
I will vote for the proposal below.↓ Thank you！
I recommend for you to upvote this idea in Box Pulse or post others feedback/idea to help us shape the future of Box.
Dear 
Thank you so much for your understanding and for taking time to vote this idea to help us improve our features and services. Have a good one! 
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