Using Box with an alternate browser, computer or network
Temporarily disabling any internet security/firewall programs to test whether they conflict with Box (note: you may need clearance/assistance from your organization’s IT department/helpdesk to do this)
I think I'm having the same, or a similar, issue. When trying to download from https://app.box.com/embed/folder/########### (I'm a salesforce admin) our users cannot download either (even when outside of a salesforce iframe) and we get the following console error: "Blocked autofocusing on a <input> element in a cross-origin subframe." but if I remove the "/embed" portion of the url so that it reads https://app.box.com/folder/########### the downloads work just fine.
This would be something our Box Support team would like to investigate with you and may require specific account information. I've gone ahead and created a ticket for you so that an agent can work directly with you on looking into this.
In case anyone else has my issue, here's what my problem was. Turns out the "/embed" route was just having errors due to cacheing after first trying to access from within Salesforce where our box settings subdomain field had accidentally been cleared out. Thanks so much France!
I am having a similar issue with an embedded Box widget. It was working fine, but in the past month the download button has stopped working (for me and for anyone around the world visiting the page). Nothing else has changed. Why is this happening and is there a way I can fix this?