When did the problem start?
You could try to use a backup created by Registry Recycler. I assume it removed too much.
Have you tried allowing the specific app through the Firewall? Control Panel\All Control Panel Items\Windows Firewall\Allowed apps
Have you tried resetting your Firewall? Control Panel\All Control Panel Items\Windows Firewall\Restore defaults
Have you tried the built-in troubleshooter for programs?
Open control panel, search for troubleshoot.
Thats why I mentioned the built-in troubleshoot program, I suspect there is a problem with the firewall.
Apologies for not being clear about that.
I looked at my restore points again and I found windows did an automatic restore point a few weeks ago
I used the restore point and its working fine now.
lucky me.