Mac Remote Desktop Connection Windows 8.1 Update, Tip: Remote Desktop Connection cannot verify the identity of the computer you want to connect to

Find a solution online:

Solution
Enable RDP Security Layer in Group Policy on the machine:

Verify that the firewall allows Remote Desktop connections with RDP (Port 3389)
Click Start>run
Type gpedit.msc and click "OK"
Result:the Group Policy Editor would open
In the left hand side bar, expand computer configuration>administrative templates>windows components>remote Desk Top Services>remote Desktop Session Host
Select "Security"
Change "Require with specific security layer for Remote Desktop (RDP) connection ' to Enabled ' and select ' RDP ' in the Op tions pane.
Change ' Require user authentication for remote connections by using the Network level Authentication ' to ' Disabled.
Close Group Policy Editor and reboot the changes to take effect.