We are running CRM 2011 with IFD and ADFS on our internal network. Remote users (not VPN connected) are continually prompted to enter their credentials frequently throughout the course of the day. This is extremely frustrating for them to have to stop what they are doing to re-enter their credentials.This also happens to in house clients as well on our LAN. It appears to be happening in both the Outlook client and web client.
In IIS, Kernel-Mode authentication is enabled.