When you attempt to map a Share Point Library to a Windows 10 computer you get the following error message.
System error 224 has occurred.
Access Denied. Before opening files in this location, you must first add the web site to your trusted sites list, browse to the web site, and select the option to login automatically.
Most solutions point you to the same two default requirements which I am sure you have already done. Namely
1. Add https://*.sharepoint.com &/or https://yourdomainname.sharepoint.com to Trusted sites in IE Security settings
2. Login to your Sharepoint site &/or Office.com in IE and select the checkbox " Keep me signed in"
There are two other not so well known resolutions.
3. Ensure that the WebClient service is running and is logged on as " Local Service"
4. In IE Security tab for the Internet Zone UnCheck the box for ‘Enable Protected Mode’