Microsoft has implemented additional security mechanisms in Windows to prevent accidental or intentional file or folder modification by not allowing users other than owner of file or folder to access it. Hence in case you need to access, modify or delete such files or folder you need to assign rights or permission to respective users.
Please note that on some systems the “Apply” button will remain greyed out after editing the port settings. In this case the “OK” button will serve to save the settings.

To allow saving ConnectCNC port configurations:
With the Administrator logged in:
Using “My Computer” or the Windows Explorer, navigate to the folder holding the ConnectCNC.exe file. The default is “C:\Program Files\CNC Consulting\EditCNC” or “C:\Program Files\CNC Consulting\ConnectCNC\”.
Windows 64bit users go to “C:\Program Files (x 86)\CNC Consulting…” Right-click on the file port.cfg
In the menu that pops up click “Properties”
Under the “General” tab make sure “Read-only” is NOT checked.
Click “Apply” if it is not greyed out
Click “OK”

Right click “ConnectCNC.exe” and select Properties.
Click the “General” tab.
Make sure the “Read Only” and “Hidden” checkboxes are NOT checked.
Click the “Compatibility” tab.
Check “Run this program in compatibility mode for” Windows XP Service Pack 3)
Check “Run this program as administrator”
Click the “Security” tab.
Edit the user permissions to ensure that all users can Read & execute, Read, Write.
If you are not familiar with this process, please have a reputable tech do it for you.