The behavior you are expecting there should be expected since Windows 10 is not yet fullysupported. Check below:
Internal Hardware (Microsoft Windows 10)
We are waiting for Microsoft to publish requirements for Microsoft Windows 10. When the requirements are available, we'll update this row.
Note :Due to changes to Microsoft Internet Explorer on Microsoft Windows 10, if users set Microsoft Internet Explorer as their default browser on Microsoft Windows 10, user must uncheck Enable Protected Mode in Internet Explorer Security settings. If users do not disable Protected Mode, they will not be able to start the Cisco Unified CM Self-Care portal from the Cisco IP Communicator Preferences menu.
Reference: http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cipc/8_6_6/Release_Notes.html#CIPC_RF_A5233D61_00
Regards
Deepak
