sharepoint keeps asking for credentials when opening documents

http://www.techrepublic.com/blog/smb-technologist/prevent-unwanted-credentials-prompts-with-sharepoint-document-libraries/


http://blogs.technet.com/b/office_integration__sharepoint/archive/2014/02/24/users-are-prompted-for-username-and-password-when-opening-an-office-file-from-a-web-server.aspx