Just a quick question , Are you using the Home version or Enterprise version of McAfee ??
If you are not sure on that , please open McAfee and let us know what is says , probably any quotes from there or a screen shot of your security center.
Sorry for the delayed response , could you please try to open the NETBIOS port and check the status of your sharing .
- Double-click the M icon in your taskbar.
- Open the Web and Email Protection drawer and select Firewall.
- Open the Ports and System Services drawer.
- Select the checkbox beside the Windows File Sharing (NETBIOS) Ports 137-139 option.
- Close McAfee SecurityCenter.